PEDS Practice: Chapter 27 Nursing Care of the Child with an Alteration in Genetics

A nursing student is reviewing information about inheritance and genetic disorders. The student demonstrates understanding of the information by identifying what as an example of a disorder involving multifactorial inheritance?

Cleft palate Cleft palate is attributed to multifactorial inheritance. Hemophilia follows an X-linked recessive inheritance pattern. Hypophosphatemic rickets follows an X-linked dominant inheritance pattern. Cystic fibrosis follows an autosomal recessive inheritance pattern.

When describing genetic disorders to a group of couples planning to have children, the nurse would identify which as an example of an autosomal dominant inheritance disorder?

Huntington disease Huntington disease is an example of an autosomal dominant inheritance disorder. Sickle cell disease, phenylketonuria, and cystic fibrosis are examples of autosomal recessive inheritance disorders

The nurse is assessing a 3-year-old boy with Sturge-Weber syndrome. Which finding is most indicative of the disorder?

Inspection reveals a port wine stain Children with Sturge-Weber syndrome will have a facial nevus, or port wine stain, most often seen on the forehead and one eye. While the child may experience seizures, retardation, and behavior problems, they are not definitive findings.

Which statement about nondisjunction of a chromosome is true?

It is failure of the chromosomal pair to separate. Nondisjunction simply means failure to separate. Nondisjunction can happen at any chromosome and is attributed to 95% of Down syndrome cases. Genomic imprinting is a different genetic disorder that is not related to nondisjunctioning.

The parent of a child diagnosed with Duchenne muscular dystrophy asks why gene therapy is not being used to treat her child. What is the best response by the nurse?

"Gene therapy remains experimental and is used only in clinical trials." Gene therapy in the United States is currently experimental and is used only in clinical trials. Clinical trials have resulted in minimal success. No documentation supports the statement that gene therapy would not work for muscular dystrophy. Genetic testing is used to diagnose illness; therefore, it is widely accepted as ethical when used to diagnose disorders. Gene therapy may be viewed by some as unethical, but the nurse should provide information in a nonjudgmental manner.

A couple has just learned that their son will be born with Down syndrome. The nurse shows a lack of understanding when making which statement?

"I will alert your entire family about this so you don't have to." It is necessary to maintain confidentiality at all times, which prevents health care providers from alerting family members about any inherited characteristic unless the family member has given consent for the information to be revealed.

Which statement by the parent of a 12-month-old child diagnosed with Down syndrome shows the need for further education?

"I will need to delay any further immunizations." Down syndrome children are at higher risk for infection because of a lowered immune system. Delaying immunizations may expose the child to illnesses that could have been prevented. Down syndrome children are at greater risk for developing thyroid disorders, 1st and 2nd vertebrae disorders, and respiratory infections.

A community health nurse is visiting a 16-year-old new mother. The nurse explains to the client and her mother the genetic screening that is required by the state's law. The client asks why it is important to have the testing done on the infant. What is the nurse's best response?

"PKU, congenital hypothyroidism, and galactosemia are conditions that could result in disability or death if untreated." The first aim is to improve management, that is, identify people with treatable genetic conditions that could prove dangerous to their health if left untreated. The other answers are incorrect because genetic testing does not determine the rate of infectious disease. The other answers do not adequately explain the rationale for newborn testing.

Which statement by the nurse accurately describes the term phenotype?

"The individual's outward appearance" Phenotype is the outward characteristic of an individual. The genetic makeup of an individual is a genotype. A somatic cell is an individual cell that combines with others to form an organism. Phenotype can be determined by both homozygous genes and heterozygous genes.

Which statement by the nurse is most accurate when counseling a couple about transmitting Huntington disease from father to child?

"There is a 50% chance of transmission of the disorder because it is an autosomal dominant disorder." An offspring of an autosomal dominant disorder has a 50% chance of acquiring the gene to be affected by the disorder. Huntington disease is an autosomal dominant disorder. Female offspring of an X-linked recessive disorder have the possibility of being a carrier or of being afflicted with the disorder. With autosomal recessive disorders, there is only a 25% chance that the offspring will express the disorder.

A parent asks why a physical therapist is needed for the 6-month-old child diagnosed with Down syndrome. What is the best response by the nurse?

"To optimize the child's development and functioning" Interventional therapy is started early to promote the child's development and optimize functioning. The Down syndrome child usually meets developmental milestones at a slower pace. There is no cure for genetic disorders. Range-of-motion activities can prevent contractures; Down syndrome does not require physical therapy.

A nurse is teaching about autosomal dominant and recessive genetics. Which statement by the nurse is accurate?

"Two abnormal genes, one from each parent, are required to produce the phenotype in an autosomal recessive disorder." An autosomal recessive disorder requires two abnormal genes to outwardly express the disorder. Recessive disorders have a lower risk of phenotyping than dominant disorders. X-linked and autosomal disorders are two different classifications.

The nurse is talking with a pregnant woman who is a carrier for a genetic disorder. The woman does not have any symptoms of the disorder. The pregnant woman asks the nurse about the risk to her unborn baby. What is the most appropriate response by the nurse?

"We can only assess the potential risk after the baby's father undergoes genetic testing." When an individual is a carrier for a genetic disorder the risk can only be assessed after viewing the genetic profile of the other parent. If the child's father is not a carrier of the gene or have the disorder there is no risk for the child to have the disorder. The child, however, can be a carrier like the mother.

The nurse is teaching the parents of a 14-year-old boy who has been diagnosed with Klinefelter syndrome. Which response by the parents indicates a need for more teaching?

"We could have also had a girl with male characteristics." The couple does not understand that this disorder does not occur in females. Klinefelter syndrome is an abnormality of the sex chromosome that affects only males. Klinefelter syndrome is caused by testosterone deficiency and is treated with testosterone replacement. Cognitive impairments do occur, sometimes in the form of learning disabilities, speech or language difficulties, or attention deficits. Breast reduction surgery may be necessary if gynecomastia occurs.

The nurse is describing some of the developmental milestones the mother of a 3-month-old boy with Down syndrome can expect to see in her child. Which statement describes the milestones that are expected in a child with Down syndrome?

"You can expect him to eat with his hands by age 12 months." Children with Down syndrome will accomplish eating with their hands by about 12 months of age. They will develop the skills of typical children, but at an older age. The child with Down syndrome will speak in sentences at 24 months rather than 21 months. Bladder training would occur by 48 months rather than 32 months. A child with Down syndrome will crawl at 11 months rather than 9 months.

A woman who has a recessive gene for sickle cell anemia marries a man who also has a recessive gene for sickle cell anemia. Their first child is born with sickle cell anemia. The chance that their second child will develop this disease is:

1 in 4. Autosomal recessive inherited diseases occur at a 1-in-4 incidence in offspring. The possibility of a chance happening does not change for a second pregnancy.

The nurse recognizes that which individual or couple would most benefit from obtaining genetic counseling?

23-year-old female, 25-year-old-male, both with family history of sickle cell disorder A family history of sickle cell disorder increases the risk of passing the disorder to offspring; genetic counseling would benefit this couple most. The usual standard for counseling for pregnancy loss is two or more, not a single loss. A normal alpha-fetoprotein screening is not a criterion for genetic counseling. All ages listed here do not exceed the criterion for advanced maternal or paternal age.

A nurse is counseling a couple who report that they are both carriers for a condition. The medical history reveals neither of them have symptoms of the condition. In the event this couple conceives a child. what is the likelihood they will have a child who will have the disorder?

25% When an individual is a carrier for a disorder they have one normal gene and one abnormal gene. They do not demonstrate the symptoms of the disorder. In the event they reproduce with an individual with the same pattern, they will have a 25% chance of conceiving a child with the disorder. There is a 50% chance they will conceive a child who like them is a carrier for the disorder.

A young couple expecting their first child comes to the clinic concerned that their baby will be born with Down syndrome. The nurse informs the couple that the incidence of Down syndrome is highest in women older than what age?

35 years The incidence of Down syndrome increases with advanced maternal age and is highest if the mother is older than 35 years and the father is older than 55 years.

A nurse is counseling a couple who have a 5-year-old daughter with Down syndrome. The nurse recognizes that their daughter's genome is represented by which chromosone combination?

47XX21+ In Down syndrome, the person has an extra chromosome 21, so this is abbreviated as 47XX21+ (for a female) or 47XY21+ (for a male). 46XX is a normal genome for a female. The abbreviation 46XX5p- is the abbreviation for a female with 46 total chromosomes but with the short arm of chromosome 5 missing (Cri-du-chat syndrome).

A pregnant woman has a child at home who has been diagnosed with neurofibromatosis She asks the nurse what she should look for in the new baby that would indicate that it also has neurofibromatosis. What sign should the nurse instruct the woman to look for in the new baby?

Café-au-lait spots Physical assessment may provide clues that a particular genetic condition is present in a person and family. Family history assessment may offer initial guidance regarding the particular area for physical assessment. For example, a family history of neurofibromatosis type 1, an inherited condition involving tumors of the central nervous system, would prompt the nurse to carry out a detailed assessment of closely related family members. Skin findings such as café-au-lait spots, axillary freckling, or tumors of the skin (neurofibromas) would warrant referral for further evaluation, including genetic evaluation and counseling. A family history of familial hypercholesterolemia would alert the nurse to assess family members for symptoms of hyperlipidemias (xanthomas, corneal arcus, abdominal pain of unexplained origin). As another example, increased urination could indicate type 1 diabetes. Projectile vomiting is indicative of pyloric stensosis.

Parents have just given birth to a child diagnosed with trisomy 21 (Down syndrome). The couple are parents of 3 other children under the age of 8 years old with no genetic disorders. What would be a priority nursing diagnosis at this time?

Deficient knowledge regarding trisomy 21 Based on the child just being born and the parents dealing with 3 other children, the highest priority is Deficient knowledge regarding trisomy 21, followed by interrupted family processes.

A pregnant woman undergoes a triple/quadruple screen at 16 to 18 weeks' gestation. What would the nurse suspect if the woman's level is decreased?

Down syndrome Decreased levels might indicate Down syndrome or trisomy 18. Sickle cell anemia may be identified by chorionic villus sampling. Levels would be increased with cardiac defects, such as tetralogy of Fallot. It does not detect respiratory disorders.

A 45-year-old man has just been diagnosed with Huntington disease. He and his wife are concerned about their four children. What will the nurse explain about the children's possibility of inheriting the gene for the disease?

Each child will have a 50% chance of inheriting the disease. Huntington disease is an autosomal dominant disorder. Autosomal dominant inherited conditions affect female and male family members equally and follow a vertical pattern of inheritance in families. A person who has an autosomal dominant inherited condition carries a gene mutation for that condition on one chromosome pair. Each of that person's offspring has a 50% chance of inheriting the gene mutation for the condition and a 50% chance of inheriting the normal version of the gene. Based on this information, the choices of 25%, 75%, or no chance of inheriting the disease are incorrect.

The nurse is caring for a 1-year-old boy with Down syndrome. Which intervention would the nurse be least likely to include in the child's plan of care?

Educating parents about how to deal with seizures It is unlikely that the parents will need to know how to deal with seizures. It will be helpful to provide parents with growth and developmental milestones that are unique to children with Down syndrome. More than 60% of children with Down syndrome have hearing loss, so promoting annual vision and hearing tests is the priority intervention. Special diets are usually not necessary; however, a balanced, high-fiber diet and exercise are important because constipation is frequently a problem.

Which sign or symptom reported by a parent would not be consistent with a child diagnosed with CHARGE syndrome?

Enlarged testes Hypogonadism, not enlarged testes, is a sign consistant with CHARGE syndrome. Visual and hearing deficiencies are common among CHARGE syndrome children. Because of narrowing of the throat passage, the child may experience coughing when drinking fluids. This can be an indication of aspiration.

When counseling potential parents about genetic disorders, which statement would be appropriate?

Environmental influences may affect multifactorial inheritance. It is difficult to predict with certainty the incidence of genetic disorders because in some disorders, more than one gene is involved and environmental insults may play a role (cleft palate, for example).

An 18-year-old male is diagnosed with Klinefelter syndrome. What signs and symptoms are consistent with this diagnosis?

Hypogonadism and gynecomastia Klinefelter syndrome affects males, causing only testosterone deficiency. Males may develop female-like characteristics such as gynecomastia and may experience hypogonadism. Decreased pubic and facial hair, along with tall stature, are characteristic of the disorder. The corresponding signs and symptoms listed in the other answer selections are not signs and symptoms of the disorder.

The nurse is assessing a 2-week-old boy who was born at home and has not had metabolic screening. Which sign or symptom indicates phenylketonuria?

Musty or mousy odor to the urine Children with phenylketonuria will have a musty or mousy odor to their urine, as well as an eczema-like rash, irritability, and vomiting. Increased reflex action and seizures are typical of maple sugar urine disease. Signs of jaundice, diarrhea, and vomiting are typical of galactosemia. Seizures are a sign of biotinidase deficiency or maple sugar urine disease.

An infant with craniosynostosis from Apert syndrome becomes lethargic and starts to vomit. What is the priority nursing intervention?

Notify the doctor and prepare for surgery The child is exhibiting signs and symptoms of increased intracranial pressure related to premature fusing of the skull joints. Surgery will be needed to relieve the pressure. IV dextrose is contraindicated with increased intracranial pressure. Waiting 1 hour to reassess may lead to brain damage and death. Monitoring intake and output is needed with a hospitalized child but is not the priority intervention based on presentation of symptoms.

The nurse is performing a physical examination on a 1-week-old girl with trisomy 13. What would the nurse expect to assess?

Observation reveals a microcephalic head. Children with trisomy 13 have microcephalic heads with malformed ears and small eyes. Severe hypotonia, hypoplastic fingernails, and clenched fists with index and small fingers overlapping the middle fingers are typical symptoms of trisomy 18.

The nurse is examining an 8-year-old boy with chromosomal abnormalities. Which sign or symptom suggests the boy has Angelman syndrome?

Observation shows jerky ataxic movement Angelman syndrome is characterized by jerky ataxic movements, similar to a puppet's gait. Hypotonicity is a symptom of Angelman syndrome as well as Prader Willi syndrome, and Cri-du-chat. Cleft palate is a symptom of velo-cardio-facial/DiGeorge syndrome.

The parents of a 3-month-old bring their baby to the clinic with vomiting, irritability, and an eczema-like rash. The nurse notices that the infant's urine smells musty. The parents state the baby was born at home and this is the first time the infant has been seen by a health care practitioner. The nurse is aware that this infant is most likely exhibiting sign of which disorder?

Phenylketonuria Phenylketonuria (PKU) is a deficiency in a liver enzyme leading to inability to process the essential amino acid phenylalanine properly. Phenylalanine is found mostly in protein-containing foods such as meat and milk (including breast milk and formula). The disease has no symptoms at birth. Most cases are identified before symptoms are present due to newborn screening (PKU is screened for in all states). Since this child was born at home the disease was not diagnosed.

A pregnant woman of Jewish descent comes to the clinic for counseling and tells the nurse that she is worried her baby may be born with a genetic disorder. Which disease does the nurse identify to be a risk for this client's baby based on the family's ancestry?

Tay-Sachs Sickle cell anemia occurs most often in African Americans, Tay-Sachs disease occurs most often in people of Jewish ancestry. B-thalassemia is a blood dyscrasia that occurs frequently in families of Greek or Italian heritage. Down syndrome is not attributed to Jewish ancestry

A baby is born with what the primary care provider believes is a diagnosis of trisomy 21. This means that the infant has three number 21 chromosomes. What factor describes this genetic change?

The client has a nondisjunction occurring during meiosis. During meiosis, a pair of chromosomes may fail to separate completely, creating a sperm or oocyte that contains either two copies or no copy of a particular chromosome. This sporadic event, called nondisjunction, can lead to trisomy. Down syndrome is an example of trisomy. The mother does not have a mutation of chromosome 21, which is indicated in the question. Also, trisomy does not produce a single X chromosome and infertility. Genes are packaged and arranged in a linear order within chromosomes, which are located in the cell nucleus. In humans, 46 chromosomes occur in pairs in all body cells except oocytes and sperm, which contain only 23 chromosomes.

The student nurse is studying the genetics of clients who are seeking assistance from a genetic counseling center. The student nurse notes monogenic disorders have which characteristic?

The disorders are considered single-gene Principles of inheritance of single-gene disorders are the same that govern the inheritance of other traits, such as eye and hair color. These patterns occur because a single gene is defective and the disorders that result are referred to as monogenic or, sometimes, mendelian disorders.

A woman with both heart disease and osteoarthritis has come to the genetics clinic for genetic screening. What would the nurse know about these two diseases?

They are multifactorial Genomic or multifactorial influences involve interactions among several genes (gene-gene interactions) and between genes and the environment (gene-environment interactions), as well as the individual's lifestyle

The results of a woman's quadruple marker screen show that her alpha-fetoprotein (AFP) blood level is more than twice the value of the mean for that gestational age. The nurse recognizes that this finding is most strongly associated with:

a neural tube disorder. AFP in maternal blood is elevated more than twice the value of the mean for the gestational age if a neural tube disorder such as myelomeningocele is present; it is decreased in amount if the fetus has a chromosomal disorder such as trisomy 21. Lower than normal levels of unconjugated estriol may also indicate a woman is at high risk for having a baby with Down syndrome. An elevated level of human chorionic gonadotropin (hCG) indicates presence of a trisomy disorder.

The nurse has asked the client for a family history. This nursing assessment is the first step in which aspect of genetic counseling?

establishing a pedigree Nursing assessment of the client's health includes obtaining and recording family history information in the form of a pedigree. This is a first step in establishing the pattern of inheritance. The other answers are incorrect because the pedigree is the nursing assessment. A nursing assessment of a family history does not answer the client's genetic questions or the family's relationship questions.

A client who is 37 years of age presents to the health care clinic for her first prenatal checkup. Due to her advanced age, the nurse should prepare to talk with the client about her increased risk for what complication?

genetic disorders Women over the age of 35 are at increased risk of having a fetus with an abnormal karyotype or other genetic disorders. Gestational diabetes, an incompetent cervix, and preterm labor are risks for any pregnant woman.

In attempting to determine what caused a child to be born with deafness, the nurse can explore with the mother if she had exposure to a teratogenic agent during which weeks' gestation?

weeks 3 to 8 During the embryonic stage, weeks 3 to 8, the conceptus grows rapidly as all organs and structures are forming. During this critical period of differentiation the growing embryo is most susceptible to damage from external sources, including teratogens.

The nurse is examining a 2-year-old girl with VATER association. Which sign or symptom should be noted?

History of corrective surgery for anal atresia The nurse would likely find records of corrective surgery for anal atresia because it is a symptom of VATER association. The nurse may observe that the child has a hearing deficit, underdeveloped labia, and a coloboma, along with heart disease, retarded growth and development, and choanal atresia if the child had CHARGE syndrome.

A woman is to undergo chorionic villus sampling as part of a risk assessment for genetic disorders. What statement would the nurse include when describing this test to the woman?

"A small piece of tissue from the fetal placenta will be removed and analyzed." Percutaneous umbilical cord sampling involves the insertion of a needle into the umbilical vessel. An amniocentesis involves the collection of amniotic fluid from the amniotic sac. Fetal nuchal translucency involves the use of intravaginal ultrasound to measure fluid collected in the subcutaneous space between the skin and cervical spine of the fetus. Chorionic villus sampling involves the removal of a small tissue specimen from the fetal portion of the placenta.

The nurse prepares a couple to have a karyotype performed. What describes a karyotype?

a visual presentation of the chromosome pattern of an individual A karyotype is a photograph of a person's chromosomes aligned in order.

A 47-year-old woman with osteoarthritis and hypertension is diagnosed with breast cancer. She tells the nurse that her mother also suffered from osteoarthritis and hypertension and she developed breast cancer at the age of 51 years. The nurse explains that this could be a result of:

multifactorial inheritance. Many birth defects and common health conditions such as heart disease, high blood pressure, cancer, osteoarthritis, and diabetes occur as a result of interactions of multiple gene mutations and environmental influences. Thus, they are called multifactorial or complex conditions. The other answers are incorrect because X-linked conditions, autosomal recessive conditions, and autosomal dominant conditions are not caused by the interactions of multiple gene mutations and environmental influences.

A nurse is describing the underlying cause of trisomy 21 to a group of parents, integrating knowledge that the disorder is due to:

nondisjunction. Trisomy 21 is a disorder caused by nondisjunction or error in cell division. It is not due to the loss of a portion of the chromosome (deletion), an extra segment being present (duplication), or transfer of one part of the chromosome to another (translocation).

A woman has just given birth to a healthy term newborn. Upon assessing the umbilical cord, the nurse would identify what findings as normal? Select all that apply.

one vein two arteries The normal umbilical cord contains one large vein and two small arteries.

A nurse teaching a couple says that when X-linked recessive inheritance is present in a family, the genogram will reveal that:

only males in the family have the disorder. When X-linked recessive inheritance is in a family, a genogram will reveal only males in the family with the disorder, a history of girls dying at birth for unknown reasons, unaffected sons of affected men, and parents of affected children not having the disorder.

A young couple who underwent preconceptual genetic counseling and testing have learned that they are at high risk for having a child with Down syndrome. They have decided not to have children. What would be the most appropriate response for the nurse to give?

"I understand. In case you would like to discuss this further with a genetic counselor, here is the contact information for the genetic counseling center. Even if a couple decides not to have more children, the nurse should be certain they know genetic counseling is available for them should their decision change. It is never appropriate for a health care provider to impose his or her own values or opinions on others. Individuals with known inherited diseases in their family must face difficult decisions, such as how much genetic testing to undergo or whether to terminate a pregnancy that will result in a child with a specific genetic disease. The nurse should be certain couples have been told all the options available to them so they can think about the options and make their decision by themselves. The nurse should help them to understand nobody is judging their decision because they are the ones who must live with the decision in the years to come.

Which statement by a parent regarding mitochrondrial disorders requires further education?

"It is passed from female to female. That's why my son cannot be affected." Mitochondrial disorders usually are inherited from the mother and affect offspring regardless of sex. Mitochondrial disorders are progressive, and onset of signs and symptoms can occur from infancy to adulthood. The disorder affects cells that require high levels of energy.

The parents of a child diagnosed with Tay-Sachs inquire about progression of the disorder. Which statement by the nurse is accurate?

"The child will experince decreased muscular and neurologic functioning until death occurs." This is an irreversible progressive disorder that affects the functioning of muscles and the neurologic system. Symptoms cannot be controlled by changes in the diet, and medication therapy will not reverse symptoms nor prolong life. Medication will be used to treat symptoms and provide comfort measures.

A 25-year-old woman who recently underwent genetic testing has just learned that she is heterozygous dominant for Huntington disease. Her husband, however, who also underwent the testing, is free from the trait. What are the odds that the couple will have a child who will inherit the disorder?

50% If a person who is heterozygous or has a dominant illness gene opposing a recessive healthy gene mates with a person who is free of the trait, the chances are even (50%) a child born to the couple would have the disorder or would be disease and carrier free (that is, carrying no affected gene for the disorder).

Which couple would the nurse document as being at highest risk for having a child with a trisomy 21 disorder?

A couple in their late 40s Race and socioeconomic status are not related to increased trisomy disorders. Although lack of prenatal care can contribute, advanced maternal age (older than age 35) introduces the highest risk for a trisomy disorder.

A child admitted for gastritis and vomiting has a medical history of medium-chain acyl-coA dehydrogenase deficiency (MCAD). What is the priority action by the nurse?

Administer IV dextrose per orders MCAD children lack the enzyme needed to metabolize fatty acids. They have frequent episodes of hypoglycemia as a result of the disorder. Because the child is vomiting, frequent small meals would not be tolerated. The child needs IV dextrose to combat hypoglycemia. Dairy products do not affect the child's metabolic disorder; although they could cause further issues with gastritis, this would not be the priority intervention. This disorder is not associated with thiamine deficiency.

The nurse is assessing a 3-month-old boy with abnormally small vertebrae who has had a colostomy. Which assessment finding would suggest the child has VATER association?

Assessment shows the child was born with only one arm. Being born with only one arm is an associated abnormality of VATER association (also referred to as VACTERL association, the additional C and L standing for cardiac and limb abnormalities). Colobomas and microphthalmos are symptoms of CHARGE syndrome. A large forehead and down-slanting eyelids are indicative of Apert syndrome. Caudal narrowing of the spinal canal is a symptom of achondroplasia.

Upon assessment, the nurse notices that the infant's ears are low-set. What is the priority action by the nurse?

Continue to assess the infant to look for other abnormalities Continue to assess for major and minor congenital anomalies because major anomalies may require immediate medical attention. Three or more minor anomalies increase the chance of a major anomaly. Low-set ears can be a symptom of a variety of genetic disorders. Mentioning Down syndrome without further investigation can cause undue stress in parents. The infant may not need cardiac monitoring; further assessment will provide clues. Diagnostic testing is needed to determine whether the child is afflicted with a metabolic disorder.

Nondisjunction of a chromosome results in which diagnosis?

Down syndrome When a pair of chromosomes fails to separate completely (nondisjunction) the resulting sperm or oocyte contains two copies of a particular chromosome. Nondisjunction can result in a fertilized egg having trisomy 21 or Down syndrome. Huntington disease is one example of a germ-line mutation. Duchenne muscular dystrophy, an inherited form of muscular dystrophy, is an example of a genetic disease caused by structural gene mutations. Marfan syndrome is a genetic condition that may occur in a single family member as a result of spontaneous mutation.

The nurse is caring for a newborn girl with galactosemia. Which intervention will be necessary for her health?

Eliminating dairy products from the diet Galactosemia is a deficiency in the liver enzyme needed to convert galactose into glucose. This means the child will have to eliminate milk and dairy products from her diet for life. Adhering to a low phenylalanine diet is an intervention for phenylketonuria. Eating frequent meals and never fasting is an intervention for medium-chain acyl-CoA dehydrogenase deficiency. Maple sugar urine disease requires a low-protein diet and supplementation with thiamine.

The incidence of Down syndrome is 1:1600 in women older than 40 years of age, compared with 1:100 in women younger than 20 years.

False The likelihood of having a baby with Down syndrome is around 1 in 1,000 in women younger than age 30, 1 in 353 at age 35, 1 in 85 at age 40, and 1 in 35 at age 45.

After teaching a class of students about genetics and inheritance, the instructor determines that the teaching was successful when the students identify this as the basic unit of heredity.

Gene A gene is the basic unit of heredity of all traits. A chromosome is a long, continuous strand of DNA that carries genetic information. An allele refers to one of two or more alternative versions of a gene at a given position on a chromosome that imparts the same characteristic of that gene. An autosome is a non-sex chromosome.

A couple wants to start a family. They are concerned that their child will be at risk for cystic fibrosis because they each have a cousin with cystic fibrosis. They are seeing a nurse practitioner for preconceptual counseling. What would the nurse practitioner tell them about cystic fibrosis?

It is an autosomal recessive disorder. Cystic fibrosis is autosomal recessive. Nurses also consider other issues when assessing the risk for genetic conditions in couples and families. For example, when obtaining a preconception or prenatal family history, the nurse asks if the prospective parents have common ancestors. This is important to know because people who are related have more genes in common than those who are unrelated, thus increasing their chance for having children with autosomal recessive inherited condition such as cystic fibrosis. Mitochondrial inheritance occurs with defects in energy conversion and affects the nervous system, kidney, muscle, and liver. X-linked inheritance, which has been inherited from a mutant allele of the mother, affects males. Autosomal dominant is an X-linked dominant genetic disease.

A couple has just learned that their unborn son has a chromosome disorder that results in an extra X chromosome. The primary care provider explains that secondary sex characteristics will not develop in this child at puberty and that his testes will remain small and produce ineffective sperm. The nurse recognizes that this child likely has:

Klinefelter syndrome. Infants with Klinefelter syndrome are males with an extra X chromosome. At puberty, secondary sex characteristics do not develop; the child's testes remain small and produce ineffective sperm. Turner syndrome occurs in females and is characterized by only one functional X chromosome. Fragile X syndrome is an X-linked disorder in which one long arm of an X chromosome is defective, which results in inadequate protein synaptic responses; it results in cognitive challenges in males. Down syndrome (trisomy 21) is characterized by an extra chromosome at chromosome 21.

A nurse is assessing a child diagnosed with Sturge-Weber syndrome. What finding would the nurse expect to find when assessing the skin?

Port wine stain Facial nevus or port wine stain is most often seen on the forehead and on one side of the face. Café-au-lait spots are commonly associated with neurofibromatosis. Tumors are associated with tuberous sclerosis and neurofibromatosis. Pigmented nevi are associated with neurofibromatosis.

What is the main purpose of nurses having basic genetic knowledge?

To provide support and education to families The purpose of the nurse knowing about basic genetics is that it helps her to provide support and education to families. Nurses can advocate for a cure, but this is not the main purpose of attaining basic knowledge of genetics. Providing a medical diagnosis is beyond the scope of practice for a nurse. It would be impossible for the nurse to understand all genetic disorders; it is more reasonable for the nurse to be familiar with the most common genetic disorders.

A woman is to undergo karyotyping. The nurse best explains this testing as:

a picture-like analysis of the number, form, and size of the woman's chromosomes. Karyotyping is a pictorial analysis of the number, form, and size of an individual's chromosomes. Genome is a representation of a person's genetic blueprint. Genotype refers to the specific genetic makeup or gene pairs inherited from one's parents. Phenotype refers to the observed outward characteristics of an individual.

There are many steps in the process of genetic counseling and testing. Put these steps in the correct chronological order from first to last. All options must be used.

assessment of family history physical examination of parents nuchal translucency screening amniocentesis explain results of genetic testing support couple in adjusting to diagnosis The correct order is as follows: 1) assessment of family history; 2) physical examination of parents; 3) nuchal translucency screening; 4) amniocentesis; 5) explain results of genetic testing; 6) support couple in adjusting to diagnosis

Cystic fibrosis is an example of which type of inheritance?

autosomal recessive Cystic fibrosis is an autosomal recessive inherited condition. Huntington disease would be an example of an autosomal dominant inherited condition. Hemophilia is an X-linked recessive inherited condition. Cleft lip is a multifactorial inherited condition.

A nurse is preparing a presentation for a group of nurses about genetic discoveries and advances. When discussing this topic, the nurse would most likely include which topic area related to the potential for misuse?

individual risk profiling and confidentiality Individual risk profiling based on an individual's genetic makeup can raise issues related to privacy and confidentiality. Gene replacement therapy for defective genes and a greater emphasis on looking at the causes of disease are considered benefits associated with genetic advances. Rapid, more specific diagnosis of diseases would be possible.

The nurse is developing a presentation for a community group of young adults discussing fetal development and pregnancy. The nurse would identify that the sex of offspring is determined at the time of:

fertilization. Sex determination occurs at the time of fertilization. Meiosis refers to cell division resulting in the formation of an ovum or sperm with half the number of chromosomes. The morula develops after a series of four cleavages following the formation of the zygote. Oogenesis refers to the development of a mature ovum, which has half the number of chromosomes.

Girls with Turner syndrome will usually exhibit:

short stature. Girls with Turner syndrome usually have a single X chromosome, causing them to have short stature and infertility. Persons with sickle cell anemia have painful joints. Color blindness occurs in persons diagnosed with Huntington disease, and they may exhibit chorealike movements. Progressive dementia occurs in early-onset familial Alzheimer disease

Nurses are expected to know how to use the first genetic test. What is it?

the family history The family history is considered the first genetic test. It is expected that all nurses will know how to use this genetic tool. The other answers are incorrect because the developmental, physical, and psychosocial assessments are not the first genetic test.

While talking with a pregnant woman who has undergone genetic testing, the woman informs the nurse that her baby will be born with Down syndrome. The nurse understands that Down syndrome is an example of a:

trisomy numeric abnormality. Down syndrome is an example of a chromosomal abnormality involving the number of chromosomes (trisomy numeric abnormality), in particular chromosome 21, in which the individual has three copies of that chromosome. Multifactorial inheritance gives rise to disorders such as cleft lip, congenital heart disease, neural tube defects, and pyloric stenosis. X-linked recessive inheritance is associated with disorders such as hemophilia. Chromosomal deletion is involved with disorders such as cri-du-chat syndrome