NUR 417 Genomics in Nursing Quiz #1

Section questions chapter 8

1. The vascularity of the uterus increases and the endometrium becomes prepared for a fertilized ovum in which phase of the menstrual cycle? A.Menstrual B.Proliferative C.Endometrial D.Luteal phase 2. Fertilization usually takes place in the A.ovary. B.endometrium. C.ampulla. D.zona pellucid. 3. The process of capacitation involves A.separation of the sperm head from the tail. B.hardening of the zona pellucid to prevent other sperm from entering the ovum. C.rapid mitotic division. D.removal of the sperm head plasma membrane. 4. Monoamniotic-monochorionic twins (twins that share an amnion and chorion) are associated with A.a fetal mortality of 50%. B.a higher rate of congenital anomalies. C.a higher risk of adverse outcomes. D.All of the above 5. Dizygotic twins A.share the same phenotypes. B.do not share the same phenotypes. C.are always the same gender. D.share the same placenta. Answers: 1. B; 2. C; 3. D; 4. D; 5. B 1. Based on when fertilization occurs, the developmental stage that takes place between gestation week 9 through week 38 is called the stage. A.embryonic B.fetal C.organogenesis D.primordial 2. The three germ layers from which all tissues and organs develop are all of the following EXCEPT A.the primary germ. B.the ectoderm. C.the endoderm. D.the mesoderm. 3. The fetal heart begins to beat in which gestational week (following fertilization)? A.2 B.3 C.4 D.6 4. All internal and external structures are present in the fetus by which week? A.6 B.8 C.12 D.18 5. During week 5 the extensive growth of the head exceeds the rest of the body. This is caused by A.enlargement of the bones. B.an increase in maternal hormones. C.the rapid growth of the brain and facial structures. D.an increase in the size of the placenta. Answers: 1. B; 2. A; 3. B; 4. C; 5. D 1. Based on when fertilization occurs, the developmental stage that takes place between gestation week 9 through week 38 is called the stage. A.embryonic B.fetal C.organogenesis D.primordial 2. The three germ layers from which all tissues and organs develop are all of the following EXCEPT A.the primary germ. B.the ectoderm. C.the endoderm. D.the mesoderm. 3. The fetal heart begins to beat in which gestational week (following fertilization)? A.2 B.3 C.4 D.6 4. All internal and external structures are present in the fetus by which week? A.6 B.8 C.12 D.18 5. During week 5 the extensive growth of the head exceeds the rest of the body. This is caused by A.enlargement of the bones. B.an increase in maternal hormones. C.the rapid growth of the brain and facial structures. D.an increase in the size of the placenta. Answers: 1. B; 2. A; 3. B; 4. C; 5. D 1. The time in which a fetus is most vulnerable to malformations during the first 8 weeks of pregnancy is called the A.malformation period. B.pre-embryonic period. C.significant period. D.critical period. 2. The skin covering on the fetus, which is made up of fatty secretions from sebaceous glands and epithelial cells, is called A.vernix caseosa. B.lanugo. C.meconium. D.amnion. 3. Genetic and environmental causes of congenital anomalies are called A.environ-genetic inheritance. B.multifactorial inheritance. C.chromosomal inheritance. D.multiple gene inheritance. 4. A teratogen can be all of the following EXCEPT A.prenatal vitamins. B.maternal disease. C.medications. D.infection. 5. Chromosomal abnormalities and DNA mutations have been associated with advanced paternal age. A.True B.False Answers: 1. D; 2. A; 3. B; 4. A; 5. A 1. Components of preconception counseling include all of the following EXCEPT A.family history. B.history of preexisting conditions. C.partner's educational background. D.partner's medical history. 2. Prenatal care should ideally begin A.before the first missed menstrual period. B.after the first missed menstrual period. C.after the second missed menstrual period. D.after the third missed menstrual period. 3. Prenatal care is more than just health care. A.True B.False 4. Which of the following statements in NOT true about pregnancy loss? A.Fifty percent of pregnancies end in spontaneous abortion. B.Most cases of pregnancy loss are sporadic. C.Advance maternal age is associated with an increased risk of aneuploidy. D.Consanguinity is not considered a factor in fetal loss. 5. Recurrent fetal loss A.includes only losses when a genetic abnormality has occurred. B.does not require examining a parent's karyotype. C.is defined as having three pregnancy losses and no more than one live birth. D.has nothing to do with maternal or paternal age. Answers: 1. C; 2. B; 3. A; 4. D; 5. C

Malformation

A structural defect of an organ or larger body region. It can result from abnormal embryonic development such as a chromosomal abnormality of the gamete at fertilization. For example: Ectrodactyly - Grady Stiles also known as Lobster Boy (a circus performer) had this malformation

Multifactorial Causation

Conditions inherited because of a combination of environmental and genetic factors. - Genomics The more affected family members there are, the more likely it is to occur in other members. Example: spina bifida and cleft lip/palate.

Genetic Factors Influencing Fetal Development

Critical period: the first eight weeks of development when the embryo is most susceptible to malformations caused by teratogens. There are four classes of congenital anomalies: malformation, disruption, deformation and dysplasia. Approximately 1:33 babies is born with a birth defect.

Critical thinking chapter 7

Case 1 Carol is a second child of Donald and Pam Green. Carol's older brother George is now 3 years of age and without any health problems. Carol however is a different matter. Her parents have been concerned from birth. She had a delayed meconium stool at birth. She was also very slow to gain weight and had frequent respiratory infections and cough the first few months of life. The pediatrician at first thought this was due to George being in daycare and developing frequent upper respiratory infections. At 6 months of age Carol was admitted to the hospital with respiratory distress and pneumonia. She had never doubled her birth weight despite adequate fluid intake and she was below the 5% in height and weight on the growth chart. Her bowel movements were also bulky and foul smelling. The physicians suspected cystic fibrosis and ordered a sweat test. The result was Na+ level 85 mmol/l, which is reflective of CF. The diagnosis was a shocking revelation to the family. The family requested to speak to a geneticist for guidance. Like most cases of CF, the clinical history and physical exam along with positive sweat test made the diagnosis secure. CF is an autosomal recessive disorder and caused by a mutation on chromosome 7 with the CFTR gene. 1. What further data should the nurse gather from Donald and Pam before referring the family to a genetic specialist? 2. What are the signs and symptoms of CF? The prognosis? Is it linked to any ethnic group? 3. Donald and Pam ask the nurse how CF can be genetic if no one in their family ever had the disorder. What is the correct response? 4. Donald and Pam ask if other family members should know and be tested. What is the nurse's advice? What type of genetic testing should the nurse suggest? 5. The family have inquires about new genetic treatments for CF. Search websites and other literature to learn more about CF and new genetic treatments or research. Case 2 Ellen and Allen wanted to have children right after they were married. The couple was of Jamaican descent. Ellen became pregnant quickly but suffered a miscarriage at 10 weeks. The next pregnancy was 6 months later but the ultrasound scan at 30 weeks showed the baby was very small. The couple was not concerned since they were both of short stature and petite. However, when their daughter Helen was born at 37 weeks gestation, the couple knew something was troublesome. The neonate's length, head circumference, and weight were well below the third percentile. On physical exam, the infant also had a heart murmur and dysmorphic facial features. The child was diagnosed with complex heart defect and critical aortic stenosis and was referred for a genetic evaluation. The nurse inquired further into the family history and discovered that Ellen's sister also had several miscarriages. Her aunt also had a child who died from a heart problem and stillbirth before she had a healthy child. 1. Based on the history, what kind of Mendelian disorder could this suggest? 2. What type of genetic testing would be part of the genetic evaluation? 3. What type of response or emotions might the family experience after a birth of a child with malformations and suspected hereditary genetic disorder? How can the nurse provide support for this family situation? Case 3 Matt is the first son of June and Ryan. They have one daughter named Kyra. Kyra was quick with her developmental milestones and walked at 9 months of age. Matt seems slower in achieving his fine and gross motor developmental milestones compared to his sister. June associated it with being a boy. June took Matt to see the nurse practitioner during his 24-month-old visit. When comprising a history, June said that Matt did not walk until he was 20 months old. On observation, the nurse practitioner noted the toddler was clumsy, had enlarged calves, and when he got up from the floor, he rolled onto his hands and knees, using the chair to support some of his weight; and then he braced his arms against his legs (Gower's sign). Both the nurse practitioner and June were concerned about Matt's development. With further probing into the family history, the nurse learned June's uncle had died during his teenage years with DMD. The nurse practitioner referred Matt to a neurologist and geneticist. 1. What clues in this scenario suggest Matt has DMD? 2. What type of inheritance pattern is DMD? What type of diagnostic testing confirms the disorder? Case 4 Fred is 18-year-old high school student who is graduating and plans to attend college at the University of the Arts. He enjoys painting, sculpting, and going out with his friends. He admits to drinking alcohol at parties on the weekend. He always had good eyesight but within the last week he has noticed that his vision was blurred and the colors of the paints paler than usual. These symptoms cause his mother to bring him to see the nurse practitioner at the family health center. The nurse practitioner performed a complete history and physical exam. The family history is significant. His mother, Francis, is a healthy woman, but her brother has been blind since age of 27 years of age with optic atrophy. His mother's sister, Doris, also has serious visual problems, which first occurred when she was 45 years of age, and heart rhythm problems. Based on the presentation and history the nurse practitioner sent Fred to the eye hospital for ophthalmologist referral. At the hospital, the nurse read the report and found disk swelling (pseudoedema of the nerve fiber layer) and increased tortuosity of the retinal vessels. This combined with the history represents Leber hereditary optic neuropathy (Donnai & Reed, 2007). The ophthalmologist referred Fred to a geneticist due to his family history and clinical exam. Gradually over the next several months he has lost his vision, unable to paint and refocus his career. 1. What type of inheritance is Leber hereditary optic neuropathy? Will Fred's children be affected with the disorder? 2. What clues in history and physical exam suggest a hereditary disorder? 3. What would be an essential nursing intervention for Fred and his family? CRITICAL THINKING CHECKPOINT ANSWERS Case 1 1.Further data should include health history, which includes family history of genetic disorders; perinatal history; changes in developmental status; and history of present illness and treatments. 2.Signs and symptoms of Cystic fibrosis (CF) are seen in the newborn period or at least before 2 years of age with meconium ileus, failure to thrive, and/or frequent respiratory infections. Recurrent infections eventually leads to fibrotic change in the lungs with secondary pulmonary hypertension or cor pulmonale. The characteristic signs and symptoms of cystic fibrosis are recurrent episodes of pneumonia, constipation, weight loss, pale, foul-smelling stools, and diabetes. Infertility is also an issue with both sexes with congenital bilateral absence of vas deferens, and thick secretions of cervix and fallopian tubes. CF is a common autosomal recessive disorder in those with western European ancestry, less common in African-Americans and Asian-Americans. 3.It is autosomal recessive and skips generations; parents and perhaps other family members are carriers. 4.Yes. In most cases of CF, clinical symptoms and an abnormal sweat test confirm the diagnosis. Molecular testing to validate the mutations in the CFTR gene on chromosome 7 is desired to advise relatives regarding their carrier status, as well as prenatal testing or atypical cases. 5.Some sites on gene therapy for CF include: • http://www.cfgenetherapy.org.uk/ • http://www.genome.gov • http://www.sickkids.ca/Centres/Cystic-Fibrosis-Centre/ Case 2 1.The history of miscarriages, still births, and infants with congenital malformations in several generations might suggest autosomal dominant condition with reduced penetrance of balance chromosomal structural abnormality (Read & Donnai, 2007). 2.Chromosomal analysis on parents and child. 3.The parents respond with emotions of loss and grief, including shock, anxiety, denial, anger, and confusion. The nurse should be a patient advocate. The nurse needs to keep the family informed about possible findings, information regarding genetic tests, and consultations being arranged. In addition, encourage parent's involvement in the plan of care. The nurse should also identify support systems for the family and community recourses available. Case 3 1.Clues for DMD are being clumsy and slow to walk; Gower's sign (standing with support and bracing arms against legs because the proximal leg muscles are weak); enlarged calves (pseudohypertrophy); and positive family history (uncle with DMD). 2.X-linked recessive. 3.Muscle biopsy for an absence of dystrophin, DNA genetic testing for the mutation, tests to check whether creatine kinase levels are increased, and an EMG (not neurotransmitter problem). Case 4 1.Mitochondrial inheritance (maternal mitochondria). Mitochondrial inheritance occurs through maternal lines. Fred will not pass his mtDNA to his children. 2.The nature of the eye problem: rapid progression in the affected males in comparison to the late onset and heart problems in Fred's aunt. 3.Fred is probably in shock or denial. His life goals are altered and there are major changes in his life. The nurse provides an essential role in providing emotional support and referral to appropriate agencies and support groups.

New Mutation

De Novo: new spontaneous mutation An abrupt unforeseen condition that appears due to an error occurring during transmission of a gene. Due to increased age of the father and many mitotic divisions during the male's reproductive cycle Example: Duchene Muscular Dystrophy

Genomic imprinting

Epigenetic Genes inherited from the mother or father can result in diverse clinical distinctions. Example: Prader-Willi Syndrome, Angelman Syndrome Both are due to a deletion on chromosome 15.

Genetics

Originated from a Greek term referring to the scientific branch of biology focused on genes and heredity. In the mid 1800s Mendel popularized inheritance pattern theory through scientific experiments. Using peas plant 1953: Watson and Crick described the structure of the DNA molecule (deoxyribonucleic acid). In 2003 the entire human genome had been sequenced. Human Genome Project The 21st century will be known for genomic health care.

Innovations

Pharmacogenetics The intersection of pharmacology and genomics to enhance knowledge of drug therapeutics and side effects. Genetic Testing Allows the individuals to have information about their genetic makeup that helps them make informed decisions about reproductive options, health screening and behavioral modification to reduce the risk of developing certain diseases Sequencing of human genome has provided us with information that allows for the testing for various forms of genes. Key component: Family histories Nurses are experts at obtaining information regarding individual and family histories. The family history is a key component of understanding the role genetic information has in helping individuals and family members understand their personal risk factors.

Prenatal Care

Prenatal care includes diagnosing the pregnancy, monitoring its progress, screening, counseling and education. If at this time a genetic anomaly is detected, the woman will be referred to a genetic counselor for further treatment options.

Post test chapter 8

POSTTEST Answers: 1. B; 2. B; 3. C; 4. C; 5. A; 6. A; 7. C (actual answer is B); 8. B; 9. D; 10. D •1. During which phase of the menstrual cycle does the endometrium thicken in preparation for ovulation and fertilization? 1.Menstrual 2.Proliferative 3.Secretory 4.Ischemic •2. A couple who wants to use natural family planning to try to conceive needs to know that the ovum is considered fertile for . 1.8 hours 2.24 hours 3.2-3 days 4.1 week •3. In order for fertilization to occur, what part of the sperm must penetrate the egg? 1.Entire sperm 2.Tail 3.Head 4.Both head and tail •4. The pre-embryonic stage occurs during 1.week 3-8. 2.the week of the last monthly period (LMP). 3.the first 14 days following conception. 4.the first 4 days after fertilization. •5. The hormone primarily responsible for maintaining the pregnancy is 1.progesterone. 2.human chorionic gonadotropins (hCG). 3.human placental lactogen (hPL). 4.gonadotropins releasing hormone (GnRH). •6. A baby is born with a congenital heart defect. At what point would this anomaly occur? 1.Between the third and fifth week of development. 2.In the first 2 weeks of development. 3.During the eighth week of development. 4.14 days after fertilization. •7. Based on Nagele's rule, if the last monthly period (LMP) was 5/7/12, the expected date of birth would be 1.December 30, 2012. 2.February 14, 2013. 3.June 1, 2013. 4.August 23, 2013. •8. At what time in embryonic development do the male and female genital organs begin to differentiate? 1.Week 4 2.Week 8 3.Week 12 4.Week 18 •9. A woman with a family history of twins has a high chance of having 1.identical twins. 2.monozygotic twins. 3.triplets. 4.dizygotic twins. •10. If studies in animals or pregnant women demonstrate evidence of fetal abnormality or risk, or if the potential for fetal risk clearly outweighs any possible benefit of the drug, the Food and Drug Administration (FDA) category for this drug is 1.B. 2.C. 3.D. 4.X.

uniparental disomy

The child inherits both copies of a chromosome pair from the same parent instead of one copy from each. Example: PKU

Genomics

The concept that all conditions adversely affecting health and illness have both genetic and environmental causes. Example: HIV viral load Viral load - The amount of a virus present—the more virus present, the higher the load. HIV - influenced by environment but genetic component that explains why two individuals with the same viral load respond differently to disease and disease treatment

Question 2

The work of the Human Genome Project: A. created the rationale for genetic determinism B. provided us with the basis for personalized healthcare C. dictates which drugs will be most effective for treating cancer D. allows scientists to prove which individuals are healthiest Answer is B

Codominant

This occurs when the contributions of both alleles are visible in the phenotype or equally shown. Example: ABO bloodtypes If dad is A and mom is B, their child could be AB.

Question 4

Those nurses who are required to have a basic genetic literacy include: A. Advanced practice nurses B. Nurses who practice in specialty areas C. Nurses who practice in medical-surgical nursing D. All nurses, regardless of practice area, clinical specialty or level of education. Answer is D

Fetal development

Three trimesters 13 weeks each 9 weeks begin the fetal period Gestation is based on LMP Total is 40 weeks

Pretest chapter 8

•1. Based on the last menstrual period, a full-term pregnancy lasts how many weeks? 1.28 2.38 3.40 4.42 •2. Ovulation occurs 1.14 days after the start of the menstrual cycle. 2.14 days before the start of the menstrual cycle. 3.midway between two menstrual periods. 4.every other month. •3. The functions of the placenta include all of the following EXCEPT 1.it provides a passage of essential nutrients for the fetus. 2.it provides the exchange of metabolic and gaseous products. 3.it produces hormones necessary for fetal development. 4.it forms a barrier to microorganisms such as bacteria and viruses. •4. Identical twins are called 1.monozygotic. 2.dizygotic. 3.conjoined. 4.vanishing. •5. Based on the last monthly period, the ninth week marks the beginning of the fetal period. A.True B.False •6. Fetal movement felt by the mother around 16 to 20 weeks is called 1.lightening. 2.induction. 3.quickening. 4.dropping. •7. A congenital anomaly called a malformation is a(n) 1.interruption of normal development process. 2.alteration in form or shape resulting from mechanical forces. 3.subnormal development of tissue that often affects several organs. 4.a structural defect of an organ or larger body region. •8. An example of a numerical autosomal chromosomal abnormality such as a trisomy is 1.Turner syndrome. 2.Jacob's syndrome. 3.Down syndrome. 4.Klinefelter syndrome. •9. The purpose of preconception counseling includes all of the following EXCEPT to 1.identify risk factors for complications in pregnancy. 2.determine the best methods of contraception. 3.assess nutritional status. 4.screen for diseases that may be genetically transmitted. •10. A cause of fetal loss or demise is 1.morphologic abnormalities. 2.immunologic disorders. 3.infection. 4.All of the above PRETEST Answers: 1. C; 2. B; 3. D; 4. A; 5. A; 6. C; 7. D; 8. C; 9. B; 10. D

Pretest chapter 7

•1. When a set of parents has a child affected by an autosomal recessive disorder, the most likely recurrence risk is 1.100%. 2.50%. 3.33%. 4.25%. •2. New autosomal dominant disorder mutations in families in certain conditions have been associated with increased age of the father. A.True B.False •3. What is the risk for hemophilia A in the grandsons if their paternal grandfather has hemophilia A? 1.0% 2.50% 3.25% 4.100% •4. Which type of inheritance pattern occurs in a genetic disorder in which the phenotype appears in every generation, the normal family members transmit the gene to their offspring, and males and females are equally affected? 1.Autosomal dominant 2.Autosomal recessive 3.X-linked dominant 4.Mitochondrial •5. In Duchene muscular dystrophy, the median age of survival is 18 with most patients dying of 1.cardiac arrest. 2.ruptured aneurysms. 3.impaired pulmonary function. 4.malnutrition. •6. For a couple who have produced one child with cystic fibrosis, the risk for developing the disease for each subsequent child is 1.50%. 2.25%. 3.100%. 4.0%. •7. The newborn screen assesses primarily for metabolic and hemoglobinopathies disorders that are considered 1.autosomal recessive. 2.autosomal dominant. 3.X-linked recessive. 4.mitochondrial. •8. Mitochondrial disorders are inherited by 1.maternal side. 2.fraternal side. 3.both maternal and fraternal. 4.multifactorial. •9. Which of the following traits are never transmitted from the father to son? 1.Autosomal recessive 2.Autosomal dominant 3.X-linked recessive 4.Y-linked disorders •10. While genetic testing can identify the genetic composition of an individual, the may not be able to accurately determine what a person actually will look like; however, the can. 1.genotype; phenotype 2.phenotype; genotype 3.phenotype; allele •11. Mendelian Inheritance patterns include 1.autosomal dominate. 2.autosomal recessive. 3.multifactorial. 4.Both A. and B. •12. For an autosomal dominant disease, if two affected parents have a child, what is most likely the risk of passing on the disorder? 1.100% 2.25% 3.50% 4.75% •13. Few genes are known to be located on the Y chromosome and inherited from father to son. A.True B.False •14. If an aunt has children with her nephew, which of the following terms is used to describe the relationship? 1.Interrelatedness 2.Recessively 3.Inbreeding loop 4.Consanguinity •15. A portion of individuals with a mutated gene show no signs and symptoms of the disorder. A.True B.False •16. Any tissue with mitochondria can be affected by mitochondrial disease. A.True B.False •17. Inheritance can explain conditions like baldness and gout. A.True B.False •18. An example of co-dominance is the ABO blood group. A.True B.False •19. Genetic disorders showing anticipation demonstrate increased severity with future generations. 1.True 2.False •20. The following are true regarding X-linked dominant disorders EXCEPT 1.mutated gene is located on the X chromosome. 2.X inactivation in females modifies the affect in females. 3.affected families show excess of male offspring is 2:1. 4.disorders are relatively uncommon. Answer: 1. D; 2. A; 3. A; 4. A; 5. C; 6. B; 7. A; 8. A; 9. C; 10. A; 11. D; 12. A; 13. A; 14. D; 15. A; 16. B; 17. A; 18. B; 19. A; 20. C

Posttest chapter 7

•1. Which one of the following genetic disorders is an example of imprinting? 1.Duchene Muscular Dystrophy 2.Factor V Leiden 3.Prader-Willi syndrome 4.Tay-Sachs •2. Which one of the following symptoms is associated with Fragile X? 1.Autism 2.Obesity 3.Short stature 4.Delayed puberty •3. The newborn screen assesses primarily for metabolic and hemoglobinopathies disorders that are considered 1.autosomal recessive. 2.autosomal dominant. 3.X-linked recessive. 4.mitochondrial. •4. All of the following describes mosaicism EXCEPT 1.Somatic mosaicism can result in less severe clinical manifestation of a single gene defect 2.Disorders like Duchene muscular dystrophy , osteogenesis imperfecta and hemophilia have been associated with mosaicism 3.The mutation is present in all of the germline cells 4.The mutation is present in proportion of the gonadal cells •5. What single gene disorders can cause mental retardation? (Select all that apply.) 1.Phenylketonuria 2.Congenital hypothyroidism 3.Sickle cell disease 4.Achondroplasia •6. Consanguinity is an important issue in which inheritance pattern? 1.Autosomal dominant 2.Autosomal recessive 3.X-linked recessive 4.X-linked dominant •7. Which type of Mendelian inheritance is never transmitted from father to son? (Select all that apply.) 1.Autosomal dominant 2.Autosomal recessive 3.X-linked recessive 4.Mitochondrial inheritance •8. All of the following characteristics describe osteogenesis imperfect EXCEPT 1.the majority of the types are autosomal dominant. 2. deafness is common. 3.frequent fractures. 4.mental retardation. •9. Maple syrup urine disorder and PKU are inborn errors of metabolism, and if undiagnosed can cause all of the following EXCEPT 1.mental retardation and seizures. 2.anemia. 3.hyptonia. 4.death. •10. What are the 2 autosomal recessive disorders mandated in 50 states to screen in the newborn screen at 48 hours of life? 1.Congenital hypothyroidism and PKU 2.PKU and sickle cell disease 3.Cystic fibrosis and congenital hypothyroidism 4.Turner syndrome and Fragile X •11. Which of the following symptoms are found in Marfan syndrome? 1.Brushfield spots 2.Shield chest with wide space nipples 3.Six or more café au lait macules 4.Pectus excavatum in the sternum •12. A mom discovered that she is pregnant with a male child. There is a maternal family history of factor VIII hemophilia (X-linked recessive disorder). What will you tell this patient regarding genetic transmission? 1.There is 25% chance of transmission. 2.There is 50% chance of transmission. 3.There is 0% of chance of transmission. 4.There is 100% chance of transmission. •13. Which of the following characteristics of Fragile X is true? 1.It only affects males. 2.It is the most common hereditary cause of mental retardation. 3.Most individuals die in infancy. 4.Physical disabilities are common. •14. The physical exam of a 6-year-old identifies seven smooth-bordered, light brown lesions measuring > 0.5 cm and irregular. To confirm neurofibromatosis, what other physical findings should be present? 1.Cataracts and axillary freckling 2.Dysmorphic facial features and low set ears 3.Errors of metabolism 4.Gait anomaly and paralysis •15. Which of the following is an X-linked dominant condition? 1.Cystic fibrosis 2.Hemophilia 3.Rett syndrome 4.Alkaptonuria •16. Which of the following terms refers to the fact that different people with the same genotype can have variety in phenotype? 1.Reduced penetrance 2.Variable expressivity 3.Incomplete dominance 4.Co-dominance •17. What is the most likely explanation for a set of unaffected parents having two children with a highly penetrant, autosomal dominant disorder? (Select all that apply.) 1.Variable expressivity 2.Co-dominance 3.Germline mosaicism in one of the parents 4.Reduced penetrance •18. Autosomal dominant conditions are due to loss of a genetic function or deficiency of an enzyme in the metabolic pathway, which often presents early on in the newborn period. A.True B.False •19. Anticipation is a finding in a genetic disorder in which the severity of a phenotype increases and age of onset decreases as some genetic disorders are passed through families. A.True B.False •20. Which of the following is true about mitochondrial inheritance? 1.There is heteroplasmy or homoplasmy. 2.The mitochondria segregate randomly as cells divide. 3.Mitochondria are maternally inherited. 4.The disorder occurs in high energy organs like the heart and kidney. 5.All of the above •21. A process that can greatly affect the presentation of an X-linked phenotype in carrier females is 1.interfering mutations. 2.X-inactivation. 3.mitochondrial disorders. 4.recombination. Answer: 1. C; 2. A; 3. A; 4. C, 5. A, B; 6. B; 7. C, D; 8. D; 9. B; 10. A; 11. D; 12. B; 13. B; 14. A; 15. C; 17. C, D; 18. B; 19. A; 20. E; 21. B

Section questions chapter 7

1. Principles of single gene disorders or Mendelian disorder utilize the same principles of inheritance of other traits such as height and eye color. A.True B.False 2. Mendelian inheritance disorders or monogenic disorders are germline mutations passed onto the next generation, and they never result from spontaneous mutations. A.True B.False 3. A single gene is usually defective, which is why single gene disorders are often referred to as monogenic disorders. A.True B.False Answers: 1. A; 2. B; 3. A 1. NF1 is considered a fully penetrant disorder and does not skip generations. A.True B.False 2. Myotonic dystrophy is a cause of neonatal hypertonia. A.True B.False 3. Marfan stigmata are inclusive of skeletal anomalies, myopia, and aortic valve disorders. A.True B.False 4. If a condition skips generations it may be due to reduced penetrance. A.True B.False 5. Anticipation of disease shows decrease severity of symptoms and later onset. A.True B.False Answers: 1. A; 2. B; 3. A, 4. A; 5. B 1. PKU is a condition that can impact the neurologic function of a child. A.True B.False 2. Most autosomal recessive disorders present in adulthood. A.True B.False 3. The newborn screen only tests for PKU and congenital hypothyroidism. A.True B.False Answers: 1. A; 2. B; 3. A 1. Y-linked disorders have severe clinical significance and are fatal. A.True B.False 2. Because of X-inactivation in females, X-linked disorders can have a diverse presentation. A.True B.False 3. Hemophilia A and B will not benefit from gene therapy because a large amount of factor in the plasma is required to have beneficial results. A.True B.False 4. X-linked dominant disorders in males are often lethal. A.True B.False Answers: 1. B; 2. A; 3. B; 4. A 1. Homoplasmy refers to the presence of more than one mutation in the mitochondria. A.True B.False 2. Most of the human genome is subject to imprinting. A.True B.False 3. In X-linked inheritance, germline mosaicism does not need to be considered. A.True B.False 4. In uniparental disomy, the child inherits both copies of a chromosome pair or chromosome region from the same parent instead of one copy of a chromosome pair. A.True B.False 5. Fragile X is the most common hereditary disorder that is associated with mental retardation. A.True B.False Answers: 1. B; 2. A; 3. B; 4. A; 5. A 1. Nurses in maternal-child surroundings may be the initial health care provider to suspect a pediatric patient with a genetic condition. A.True B.False 2. Parents who have a child diagnosed with a hereditary disorder may feel symptoms of grief and loss. A.True B.False 3. Name some clues in a nurse's assessment and physical exam of patients that may alert to a hereditary genetic disorder.A. Answers:1. A; 2. A; 3. Mendelian genetic disorder, but not inclusive would be consanguinity, abnormal fetal ultrasound, cutaneous disorders, hyptonia, seizure, growth abnormalities, developmental delays, and abnormal newborn screens.

Section questions chapter 1

1. Watson and Crick A.described the structure of DNA B.were the fathers of genetic science. C.developed the human genome. D.worked in the science of eugenics. 2 Eugenics A.is the basis of human variation. B.provides us with valuable information about the superiority of one race over the other. C.is a current theory of human evolution. D.provided the rationale for the inappropriate treatment of those who had developmental disabilities. 3 The father of human genetics was A.Adolph Hitler. B.Gregor Mendel. C.James Watson. D.Francis Collins. Answers: 1. A; 2. D; 3. B 1. The work of the Human Genome Project A.created the rationale for genetic determinism. B.provided us with the basis for personalized health care. C.dictates which drugs will be most effective in treating cancer. D.allows scientists to prove which individuals are healthiest. 2. Pharmacogenomics will allow health care providers to A.avoid prescribing medications that have any side effects. B.tailor drug therapy to enhance drug effectiveness. C.decrease the number of medications an individual needs. D.decrease the cost of medications. 3. One of the uses of genetic testing is A.to totally prevent the transmission of genetic conditions. B.to provide information to individuals so they can make decisions about their personal health. C.to tell people how to lead healthy lives. D.to help people focus on the genetic basis of all illness. Answers: 1. B; 2. B; 3. B 1. The essential competencies for nursing practice in genetics/genomics A.were endorsed by over 40 professional nursing associations. B.were developed by geneticists who were experts in the field. C.are required by accrediting organizations. D.apply only to those nurses who specialize in genetics. 2. Those nurses who are required to have basic genetic literacy include A.advanced practice nurses. B.nurses who practice in specialty areas. C.nurses who practice in medical-surgical nursing. D.all nurses, regardless of practice area, clinical specialty, or level of education. Answers: 1. A; 2. D

Amniotic membrane/fluid

7 and 12 weeks gestation, amniotic fluid increase causing amnion to enlarge and bring the amnion and chorion together Form the amniotic sac Several functions •■ act as a shock absorber and cushion the fetus against severe injury. •■ act as a barrier to infection because it inhibits bacterial growth. •■ maintain a relatively constant temperature, thereby controlling the temperature of the fetus. •■ prevent adherence of the amnion to the fetus, thereby providing a medium in which the fetus can move freely. •■ provide essential enzymes for fetal lung development. •■ prevent compression of the umbilical cord. •■ allow for analysis of fetal tissue and fluids. Amniotic fluid is made up of maternal interstitial fluid by diffusion Amniocentesis - alpha fetoprotein (AFP) is a glycoprotein of fetal origin and is present in the fetal and maternal blood during pregnancy. Becomes a routine screening for prenatal diagnosis of neural tube defects and other fetal malformations High levels of AFP can indicate neural tube defects such as spina bifida /low levels of AFP can indicate Down Syndrome By 11th week, karyotyping from amniotic fluid can be performed

Normal Growth and Development

9 to 12 weeks: Can swallow and make respiratory Can curl fingers to make fist Genitalia are easily distinguishable Kidney begin producing urine Heartbeat can be heard - 120 to 160 bpm 13 to 16 weeks: Fine hair called lanugo forms on head Ossification of fetal skeleton is active Not yet felt by mother Reflex response and muscular activity begin Fetus opens mouth, makes sucking motion and swallows amniotic fluid Produce meconium in intestines In females, ovaries differentiate and contain primordial follicles 17 to 20 weeks: Limbs in proportion fo the rest of body Fetal movement can be felt by mother (quickening) Skin is now covered by vernix caseosa (cream cheese covering) Lanugo is present all over the body Uterus is formed at 18 weeks At 20 weeks myelination of spinal cord begins Testes begin to descend for male fetus IgG fetal antibodies can be detected 21 to 25 weeks: Skin is wrinkled and translucent pink red due to blood capillaries - little SubQ fat Bone marrow begins to make RBC Fetus has hand grasp and startle reflex Rapid eye movements begin IgG levels reach maternal levels Interalveolar walls of lungs begin to secrete surfactant at 24 weeks 26 to 29 weeks: Vasculature of lungs developed to provide gas exchange CNS is mature enough Eyelids open and close In males, testes descend into the inguinal canal and upper scrotum 30 to 34 weeks: Rapid increase in body fat and muscle CNS is developed enough to maintain body temperature Lungs still not fully mature Papillary light of eye is present at 30 weeks More reflexes are present Fetus begins storing calcium, iron and phosphorous 35 to 36 weeks: Exhibits spontaneous orientation to light Strong grasp reflex 37 to 40 weeks: Considered to be full term 38 to 40 weeks Males - testes are in scrotum Females - labia majora is well developed CNS developed enough to carry out some intergrative functions L/S ratio is approaches 2:1 indicating lung maturity

Prenatal Care Topics Nursing Implications.... Preconception Counseling

A comprehensive medical, surgical, reproductive, psychological, social and family and genetic history should be obtained. The father's medical, family, genetic and reproductive history should be obtained. A three generation family pedigree and carrier testing should be done for common genetic disorders. Women at risk for passing on genetic anomalies should be counseled about options (assisted reproductive technologies: preimplantation diagnosis). Nutritional assessments, prenatal vitamins and exposure to environmental teratogens should be discussed.

Critical Thinking Checkpoint chapter 1

A newly graduated professional nurse is working on a busy medical-surgical unit. She has a postoperative patient who is at risk for thrombus formation. This patient, who currently is receiving low-dose molecular heparin, is scheduled to be discharged on warfarin (Coumadin) therapy. The nurse has heard of the importance of genetic testing before implementing Coumadin therapy, but there are no such medical orders for this testing. How should the nurse proceed? ANSWERS The nurse should be aware that such genetic testing is the current standard of care. The nurse should contact the prescribing physician to determine whether he wishes to order the testing. The hospital pharmacist may be a valuable source of information for the physician.

Dysplasia

Abnormal development of tissue that often affects several organs.

Nursing implications

Accurate family history and exam remains the fundamental instrument for nurses to use in patient care. A family pedigree should be used in the family history and assessment. The maternal-child nurse will need to have knowledge related to inheritance patterns and diseases to provide competent care to families.

Deformation

An alteration in form or shape resulting from mechanical forces and occurs in otherwise healthy tissue. Example: when we used forceps to pry the baby out of the birth canal, the baby is fine but the head is squished now.

Numerical Sex Chromosomal Abnormalities

An extra or missing X or Y chromosome. Most are not diagnosed until puberty. Example: Turner Syndrome, Klinefelter Syndrome, and Jacob's Syndrome. Because of your secondary sexual characteristic are coming in

Mosaicism

An individual may have different cell lines in a particular tissue of the body occurring during an error in mitosis after fertilization of the zygote. Occurs in somatic tissue or germ cells. depicts the existence of cells that differ in their genetic constituent from other cells in the body. This occurrence would result in a person composed of two or more different cell lines. Example: Trisomy 21 (Down's Syndrome), hemophilia

Numerical Chromosomal Abnormalities

Aneuploids: an extra single or missing single chromosome. Example: Trisomy 13, 18 and 21. Becomes more frequent as maternal age increases.

Implantation

Blastocyst imbeds itself into the endometrium Trophoblast connects with the endometrium for more nourishment until it becomes the chorionic villi Endometrium increase in thickness and starts the proliferative phase Endometrium - decidua Decidua capsularis - covers the blastocyst Decidua basalis - under the implanted blastocyst that becomes the maternal part of the placenta Decidua vera - part that lines the uterine cavity Chorionic villi connect with the deciduas basalis to form the fetal part of the placenta

X linked recessive

Determined by a genetic mutation on the X chromosome. The majority are recessive and almost exclusively seen in males. Women are mostly carriers and the trait is transferred from a series of female carriers; the affected males are directly related to one another through the females. The trait is passed from an affected father to his daughters and then to 50% of his grandsons. The trait is never transferred from father to son. Example: Hemophilia, Kallman Syndrome Most famous example would be the hemophilia gene in the Romanov family - It was inherited from Tsarina Alexandria who's grandmother is Queen Victoria of England causing her son, Heir to the Romanov Alexi to obtain it •The condition is apparent almost exclusively in males. •The trait is passed from an affected male to his daughters and then to 50% of his daughters' sons. •The trait is never directly transferred from father to son. •The trait is transferred from a series of female carriers; the affected males are directly related to another through the females

Question 1

Eugenics: A. is the basis of human variation B. provides us with valuable information about the superiority of one race over another C. is a current theory of human evolution D. provided the rationale for the inappropriate treatment of those who had developmental disabilities Answer is D

Penetrance & Expressivity

Expressivity: severity of expression of the phenotype (physical presentation) of a mutation among individuals with the same disease. Variable Expressivity: the variation among members of the same family with the same disease. Examples such as neurofibromatosis (NF1) and osteogenesis imperfecta (OI) Penetrance: the chance that a specific gene mutation inherited by an individual will display physical manifestations.

Pre embryonic stage

Female reproductive cycle Ovarian and uterine cycle Ovarian: Follicular phase (days 1 to 14) FSH is released by the anterior pituitary due to the GnRH Follicle secretes estrogen Luteal phase (days 14 to 28) Mature graafian follicle appears LH cause final maturation of grassfian follicle and ovulation occurs Ovum is released near the fimbria of fallopian tubes Ruptured follicle undergoes changes and becomes the corpus luteum and secretes large amount of progesterone if pregnant. After 7 days, corpus luteum loses it function and shed if no fertilization occurs Uterine: Menstrual phase Shedding of the endometrium linings Proliferative phase Endometrium linings thicken due to increased amount of estrogen Secretory phase Endometrium become thicker and preparing for implantation Ischemic phase Few days before menses if no fertilization occurs Endometrium linings become necrotic and will later shed during the menstrual phase Ovulation occurs about 14 days prior to menstrual cycle

x inactivation

Females have to alleles for every gene on the x chromosome, whereas males have only one. During embryonic development, 75% of the genes on the x chromosome in each cell is inactivated and the remaining genes are expressed differently. How does this phenomenon affect x-linked genetic disorders? The selected genes, which are assigned as active versus nonactive in the offspring, are randomly inherited. Depending upon what genes are active in the two chromosomes, X-linked disease could have diverse presentations of the disorder in females due to the proportion of the cells that acquire the mutated allele on the active X chromosome This is epigenetics

Genetics and Nursing

ISONG and the ANA published scope and standard of practice for nurses related to genetic and genomic literacy regardless of level of education, specialty or site of practice. The AACN has identified genetics knowledge as an essential competency for BSN education. ISONG - The International Society of Nurses in Genetics ANA - American Nurses Association AACN - American Association of Colleges of Nursing Watch the movie Gattaca for eugenic and genetics

Carriers

Incomplete Dominance Inheritance One allele is expressed while another one is suppressed. Red snapdragons (RR) mated with white snapdragons (rr) created PINK snapdragons. the heterozygous phenotype is intermediate between that of either homozygote. This results in a third phenotype or a combined phenotype, which is a blend of paternal and maternal traits. Familial hypercholesterolemia

Environmental Factors (Epigenetics)

Infectious Agents - Toxoplasmosis - do not clean litter boxes!!! Herpes, Syphilis Drugs/Medication - a drug that used to treat morning sickness in England in the 1960s cause birth defect in children with limbs Alcohol - Fetal Alcohol Syndrome Tobacco - Low Birth Weight Ionizing Radiation Illicit Drugs - NAS (Neonatal Absence Syndrome) Maternal Disease - unmanaged diabetes Heavy Metals - lead, fish (high level of mercury) BPA (Bisphenol-A) - think of fat mouse all water bottles say BPA free Obesity

Disruption

Interruption of a normal developmental process. This cannot be inherited.

Critical thinking chapter 8

L.B. is a 28-year-old Caucasian woman who has polycystic ovarian syndrome and irregular periods. She recently discovered that she was pregnant. She went to her first prenatal visit and was diagnosed by ultrasound as being 11 weeks gestation. She tells the nurse that she has a family history of cleft lip—her younger brother and her uncle were born with cleft lip and palate. She also has a cousin who has Down syndrome. Two weeks ago she attended a wedding and drank three beers at the reception and later joined some friends in a hot tub. She stated that she sat in the hot tub for only 5 minutes because she started feeling nauseated. She is worried that she may have hurt her baby by drinking the beers. 1. What factors related to this pregnancy could put the fetus at risk? 2. Can testing be done to determine if the fetus has a cleft lip? If so, when? 3. What potential effect could the alcohol have on the fetus? 4. What topics should the nurse consider discussing with this woman? CRITICAL THINKING CHECKPOINT ANSWERS 1.Several factors could have put the fetus at risk including the alcohol and the hot tub. Both can be teratogenic during pregnancy. Also, more questions need to be asked in reference to L.B.'s family's history of cleft lip and Down syndrome. 2.There is no definitive test for cleft lip; however, an ultrasound scan for morphology can be done around 17-19 weeks gestation to determine if the baby has one. 3.In this case, the alcohol consumption is probably not going to have an effect on the fetus; however, if the mother continues to drink alcohol throughout her pregnancy it can cause fetal alcohol syndrome (FAS). A woman who consistently drinks alcohol during pregnancy has a 30% to 46% chance of having a fetus with long-term physical and mental defects (Lewis, 2008). It has never been determined how much alcohol is needed to cause harm so abstaining from all alcohol is recommended in pregnancy. 4.The nurse needs to discuss several topics with the woman about prenatal care and what she should expect during her pregnancy. The woman should be counseled on things such as avoiding hot tubs while pregnant; avoiding people with viral or bacterial infections; abstaining from alcohol, tobacco, or illicit drugs; checking with the physician before taking any medications; avoiding cleaning cat litter pans and bird cages during pregnancy; avoiding eating fish known to contain heavy metals such as mercury; eating a well-balanced diet and taking prenatal vitamins; getting enough exercise and sleep; and scheduling appointments for routine prenatal care

Mendelian Basics

Mendel conducted his experiments on pea plants and these "Mendelian disorders" follow the same inheritance pattern as height or eye color. However spontaneous mutation may occur. One can be either homozygous (TT) or heterozygous (Tt). An individual who possesses identical alleles for a gene is referred to as homozygous An individual who acquires two different alleles for a particular gene is referred to as heterozygous The large T's refer to dominant traits and the small t's to recessive. Genotype refers to the genetic makeup of a person, whereas the phenotype refers to the outward expression of those genes, (physical expression or physical features of the condition such as the genotype B for brown eyes and brown eyes is the phenotypes) Wild type gene is termed as the common phenotype found in a population

Embryonic stage

Nagele's rule First day of the LMP (last menstrual period), adds 7 days and then subtract 3 months Fertilization of ovum and formation of zygote as beginning of gestation (38-42 weeks) 2 to 8 weeks is embryonic period 9 weeks to 38 weeks is the fetus (fetal period) Organogenesis Ectoderm - outer primary germ layer that rise to skin, hair and naturals, central and peripheral nervous system, sensory epithelia of the eye, ear and nose and certain glands Endoderm - One of three primary germ layers of the embryo that gives rise to epithelial lining of multiple systems and parts of the liver and pancreas Mesoderm - one of three primary germ layers of the embryo that gives rise to connective tissue, bone, muscle, blood and lymph vessels, kidneys, genitals, epithelial tissue

Unstable repeat expansions

Present in everyone's genome Mostly due to cystosine, guanine, and thymine Normally there are fewer than 20-40 repeats More than that is not widely understood but may be owed to a DNA replication error (slipped mis-pairing) Example: Fragile X Syndrome, Huntington Disease.

Structural Chromosomal Abnormalities

Results from breakage of the chromosome that is repaired incorrectly or rearranged. Translocations, inversions, deletions or duplications. Example: cri du chat syndrome Microdeletions: cannot be detected without the use of fluorescent in situ hybridization (FISH). Occur de novo. Babies present as floppy and weak, with inability to suck.

Fetal Loss

SABO: spontaneous abortion. Most commonly caused by aneuploidy. (additionally or mixing of chromosomes) RPL: recurrent pregnancy loss. (3+ losses). Testing should be done on these fetuses to determine reason for loss. (karyotyping and placental evaluation)

Normal development

Start at third week and ends around eight weeks - Critical stage Body forms begins with gastrulation - specific tissues and organs Neural tube, notochord (basis of bones of head and vertebral column), coelomic spaces (form three body cavities - pericardial, pleural and peritoneal cavity), and primitive cardiovascular system and blood cells Development is cephalocaudal (top to bottom or head to toe) By eigtht weeks, all essential internal and external structures are present

Fertilization

Takes place in the ampulla (outer third of fallopian tube) Peristalsis caused by high levels of estrogen propel the fertilized ovum toward the uterus Sperm must undergo process of capacitation which is the removal of sperm head plasma membrane Once head of sperm release an enzyme, it becomes hyperactivated and cause the deterioration of the corona radiate (elongated follicular cells that radiate from the ovum) and allowing the sperm to penetrate The nucleus of sperm fuse with the nucleus called a zygote and creates a diploid (half each from father and mother) Gender is determined immediately at fertilization Zygote stage last for 14 days and travels to the uterine cavity during which cellular multiplication begins

Mitochondrial Inheritance

The mutated gene is located on the mitochondrial DNA (mtDNA). Inheritance is through maternal transmission and lost through paternal transmission. Males and females are affected equally. Variability in expression of the disorder is common. Normal and mutated mtDNA for the same allele can be in the same cell (heteroplasmy) or a mutation in the mtDNA can be present in all maternal DNA copies (homoplasmy). •All children of homoplasmy mutations will inherit the mutation. •Males will not pass on the mitochondrial disorder to their children. Example: Cardiomyopathies, Myoclonic Epilepsy

Eugenics

The proposed improvement of the human species by encouraging or permitting reproduction of only those people with genetic characteristics that are judged desirable Genetics and genomics do not exist in isolation It is not an absolute science and not all things can be reduced to genetic code. (The order of the nucleotide sequences in DNA or RNA that form the basis of heredity through their role in protein synthesis.) Example: mental hygiene movement Sterilized the mental health population Adolf Hitler and Charles Darwin's Cousin, Francis Galton was supportive of it.

Consanguinity

The relatedness of individuals who marry each other. This promotes a higher risk of rare alleles and autosomal recessive disorders in offspring. Example: Alkaptonuria It is a disorder in which the body fails to properly break down certain amino acids (tyrosine and phenylalanine). It is a defect in the HGD gene and results in brown-black-colored urine when it hits the air as well as other symptoms like arthritis in the spine later in life. This disorder was scrutinized and found in more than one-fourth of cases in which most of the parents were first cousins.

Question 3

The work of the Human Genome Project: A. created the rationale for genetic determinism B. provided us with the basis for personalized healthcare C. dictates which drugs will be most effective for treating cancer D. allows scientists to prove which individuals are healthiest Answer is B

Autosomal Recessive

These disorders are only expressed when the mutated allele is present in two copies of a gene, one from mom and one from dad. Example: Sickle Cell Disease, Cystic Fibrosis Must have two copies for the condition to exist. Only one copy is the carrier (usually no clinical manifestation)

Umbilical cord

Thick embryonic body stalk attaches the embryo to the yolk sac and contain blood vessels (AVA) Wharton's jelly - This tissue helps to protect the umbilical cord from compression and kinking. Used for prenatal genetic testing and Rh isoimmunization

Fetal circulation

Three phases: Intrauterine Blood bypassed the fetal lungs and placenta supplies oxygen to the fetus and carbon dioxide is excreted out through the placenta Transition Cutting of the umbilical cord - causes an abrupt but transient rise in arterial pressure Rise in plasma carbon dioxide and fall I oxygen cause infant to start breathing Post birth DA is closed after a few days after birth DV becomes ligamentum venosum and is longer to close FO is immediately after birth Umbilical arteries constrict

Placenta

Two layers Cytotrophoblast (inner layer) Syncytitrophoblast (outer layer) When embeded into the endometrium Placental septa allows for compartmentalization of the uteroplacental circulation Exchange of nutrients and gases are minimal during first 3 to 5 months - maternal and fetal Maternal outside - enter intervillous space through the spiral arteries of endometrium produced by maternal blood pressure Transport function 1) It provides the fetus with exchange of metabolic and gaseous products, 2) it acts as an organ of transfer, and 3) it produces the hormones necessary for fetal development and maintenance of pregnancy. Includes: simple diffusion, facilitated transport, active transport, pinocytosis, and leakage Endocrine Function Human chorionic gonadotropins ( hCG) Human placental lactogen (hPL) - human chorionic somatomammotropin Progesterone Estrogen

x linked dominant

Very rare. Expressed in the female in one gene copy. Males have more serious effects than females. Transmission is from males to all daughters but NOT to all sons. High rates of miscarriage in females and lethality in males. Affected females are more common than males and have a milder expression of the phenotype. Example: Incontinentia Pigmenti (Skin disorder), Charcot-Marie Tooth Disease (motor and sensory neuropathy) •Expressed in the female in one copy. •Males have more severe effects than females. •Transmission from male to all daughters but not to sons. •High rates of miscarriages in females and lethality in males. •Affected females are more common than males and a milder expression of the phenotype.

Autosomal Dominant

When a mutation in a single allele is sufficient to cause the disease to be present in a homozygous or heterozygous individual. Only need one copy to be affected. No carrier. If have both copies, will result in a very severe characteristics of the disease or disorder Examples include: Osteogenesis Imperfecta, Marfan Syndrome, and Myotonic Dystrophy (muscular dystrophies) - progressive weakness, myotonia, cardiac conduction abnormalities, feeding difficulties, somnolence, frontal balding, and testicular atrophy disorder of the fibrous connective tissue and defect in type 1 fibrillin, a glycoprotein encoded by the FBN1 gene. The affected individuals often present with Marfan stigmata: They are often extremely tall, with disproportion upper and lower body, arachnodactyl (spider fingers), pectus formation, joint laxity, myopia, mitral valve prolapse, and life-threatening aortic dissection (notables such as Jonathan Larson who created the Broadway, Rent, passed away due to aortic dissection)

y Linked disorder

Y-Linked or Holandric Inheritance The Y chromosome is the smallest and very few genes are known to be located on it. Only affects males. Affected males must transmit the disorder to their sons, no daughters are affected. Example: genes involved with spermatogenesis •It only affects males. •Affected males must transmit the disorder to their sons.

Pretest chapter 1

•1. Genetics is the study of A.human heredity. B.individual genes. C.the transmission of health and illness. D.mitosis and meiosis. •2. The Human Genome Project 1.was designed to identify the hereditary causes of health and illness. 2.is an ongoing effort of the U.S. Department of Health and Human Services. 3.focused solely on the science of genetics. 4.successfully mapped the entire complement of genes in humans. •3. The relevance of genetics to nursing practice A.is marginal at best. B.is limited to advanced practice nurses. C.is important to all nurses, regardless of level of education or site of practice. D.is complex and difficult to describe. •4. Nurses need to know about genetics because 1.they may have patients who ask questions that are hard to answer. 2.they may be working in places where there are no medical geneticists. 3.they have a special interest in genetics. 4.genetics knowledge is a core competency for nursing practice. •5. Illnesses that have a genetic component are limited to A.those syndromes identified by newborn screening. B.certain forms of cancer, including breast cancer. C.hereditary conditions. D.essentially all issues affecting health and illness. •6. Which of the following diagnoses does NOT have a genetic component? A.Type 2 diabetes mellitus B.Acute trauma C.Cystic fibrosis D.Rheumatoid arthritis •7. Which statement is true? 1.There are significant genetic differences between races. 2.There is more genetic variation within racial groups than between racial groups. 3.Some races are genetically inferior to other races. 4.Mental retardation has a large racial component that is genetically determined. •8. Multifactorial genetic inheritance A.includes environmental factors. B.is a result of climate change. C.is found in individuals who have sickle cell anemia. D.is only found in conditions transmitted from mother to son. •9. The Human Genome Project A.was conducted solely by the U.S. Government. B.has been completed and has no further relevance for scientific research. C.continues to be the foundation for our understanding of health and illness. D.resulted in the controversy over the use of stem cell therapy. •10. The most valuable information to determine an individual's risk for a condition with a genetic component is A.the sequencing of the breast cancer gene. B.the test for cystic fibrosis carriers. C.maternal serum screening for alpha fetoprotein. D.the family history. Answers are 1. B; 2. D; 3. C; 4. D; 5. D; 6. B; 7. B; 8. A; 9. C; 10. D

Posttest chapter 1:

•1. The most important source of genetic information can be gleaned from A.the results of genetic testing. B.newborn screening test results. C.buccal swabs. D.the family history. •2. Public health genetics/genomics information can be obtained from which website? A.CDC B.ANA C.ISONG D.NIH •3. The standards for nursing education in genetics for professional nursing programs are promulgated by: A.American Association of Colleges of Nursing B.National Institutes of Health C.Centers for Disease Control and Prevention D.American Medical Association •4. The interaction of medications and an individual's genetic makeup is the study of A.eugenics. B.genomics. C.pharmacogenomics. D.pharmacology. •5. The belief that all human responses to health and illness is caused by genetics is A.eugenics. B.genetic determinism. C.pharmacogenomics. D.genomics. 1. D; 2. A; 3. A; 4. C; 5. B