Chapter 5 Genetic and Congenital Disorders

The nurse teaches the client that ultrasonography will be used during prenatal testing to identify what type of abnormalities? chromosomal damage cytogenic abnormalities skeletal anomalies genetic mutations

skeletal anomalies

The parents of a newborn are relieved that their baby was born healthy, with the exception of a cleft lip that will be surgically corrected in 10 to 12 weeks. Which statement by the nurse to the parent's best conveys the probable cause of the newborn's cleft lip? "Your newborn's cleft lip likely results from the interplay between environment and genes." "A cleft lip can sometimes result from taking prescription drugs, even when they are taken as prescribed." "Provided one of you had the gene for a cleft lip, your baby likely faced a 50/50 chance of having one." "Though you are both healthy, you likely both carry the gene for a cleft lip."

"Your newborn's cleft lip likely results from the interplay between environment and genes."

The nurse is providing education to the parent of a male diagnosed with Marfan syndrome. The nurse knows that her teaching has been effective when the parent states which of the following? "Cardiac surgery will be used to cure the syndrome." "The most life-threatening aspects of the disorder are the chest deformities." "He will need to have his hearing checked routinely." "His participation in sports may need to be limited."

"His participation in sports may need to be limited."

Both members of a couple are carriers of an autosomal recessive trait. What will the nurse teach the couple about the risk of their child being affected? "There is a 25% risk that the child will be a carrier of this trait but not afflicted with disease." "The age of onset of most autosomal recessive disorders like PKU is later in life so it will be years before you know the child's status." "There will definitely be an abnormal protein structure that will result in muscle flaccidity when the infant tries to walk." "There is a 25% chance the child will be affected with the disease trait."

"There is a 25% chance the child will be affected with the disease trait."

The mother of a child with Turner syndrome asks the nurse what the physician meant when the disease was explained as monosomy of the X chromosome. The nurse explains the syndrome as having which of the following characteristics? "The X chromosome is absent." "There are three X chromosomes." "There are two X chromosomes." "There is one X chromosome."

"There is one X chromosome."

The parents of a newborn are relieved that their baby was born healthy, with the exception of a cleft lip that will be surgically corrected in 10 to 12 weeks. Which statement by the nurse to the parent's best conveys the probable cause of the newborn's cleft lip? "Though you are both healthy, you likely both carry the gene for a cleft lip." "Provided one of you had the gene for a cleft lip, your baby likely faced a 50/50 chance of having one." "Your newborn's cleft lip likely results from the interplay between environment and genes." "A cleft lip can sometimes result from taking prescription drugs, even when they are taken as prescribed."

"Your child's cleft lip likely results from the interplay between environment and genes." A cleft lip is considered to be a multifactorial disorder, in which both environment and genes contribute to the condition. It does not depend solely on Mendelian patterns of inheritance and is not known to result from teratogenic drugs.

The physician suspects a client may have Klinefelter syndrome. To confirm the diagnosis, the chromosome pattern would identify: 46, XY 23, XY 46, XYY 47, XXY

47, XXY

A mother who has one mutant allele on the X chromosome and one normal allele asks the nurse what the percentage is of passing it on to a daughter to be a carrier. The best response would be: 25% 100% 50% 75%

50% The common pattern of inheritance is one in which an unaffected mother carries one normal and one mutant allele on the X chromosome. This means that she has a 50% chance of transmitting the defective gene to her sons, and her daughters have a 50% change of being carrier of the mutant gene.

The nurse teaches a client about the medication classification system used to identify risk for teratogenicity. In which order will the nurse teach the client the categories are placed, from least risk to greatest for teratogenicity? Click an option, hold and drag it to the desired position, or click an option to highlight it and move it up or down in the order using the arrows to the left. 1Class X 2Class D 3Class C 4Class B 5Class A

5Class A 4Class B 3Class C 2Class D 1Class X Drugs in risk category A are the least dangerous, and drugs in category X are the most dangerous. Category X drugs are known to cause human fetal harm, and their risk to the fetus outweighs any possible therapeutic benefit. Drugs in categories B, C, and D are progressively more dangerous than drugs in category A and less dangerous than drugs in category X. Because this law does not require classification of drugs that were in use before 1983, not all drugs are classified.

Which statement is true about recessive gene inheritance? A carrier is a non-affected person with a single copy of a recessive gene. Dominant genes have less power of expression than recessive ones. X-linked recessive genes are expressed only if two X chromosomes are present. Variability of gene expression is called reduced penetrance.

A carrier is a nonaffected person with a single copy of a recessive gene. Norris, T. L., Porth's Pathophysiology: Concepts of Altered Health States, 10th ed., Philadelphia, Wolters Kluwer, 2019, Chapter 5: Genetic and Congenital Disorders, p. 85.

A woman who is considering becoming pregnant has just been exposed to an environmental toxin. The woman contacts her doctor to ask if she is now at any risk. Which response would be considered most accurate? "An infant will likely have a congenital cardiac disorder." "No negative reaction is expected." "You may have difficulty conceiving in the future." "A miscarriage of the fetus can possibly occur."

A miscarriage of the fetus Environmental influences during the first 2 weeks after fertilization may interfere with implantation and result in abortion or early resorption of the products of conception. Exposure during the pregnancy can result in a variety of congenital disorders. Sterilization is possible but is dependent on a variety of factors.

The gene responsible for a particular congenital cardiac anomaly is said to have complete penetrance. What are the clinical implications of this fact? All the individuals who possess the gene will exhibit the anomaly. Multiple alleles contribute to the defect. The anomaly is a result of polygenetic inheritance. The heart defect does not result from any other gene.

All the individuals who possess the gene will exhibit the anomaly. Penetrance represents the ability of a gene to express its function, with complete, or 100%, penetrance, ensuring that all individuals possessing the gene will experience the phenotype in question. The disorder is not necessarily the result of multiple alleles or polygenetic inheritance, and complete penetrance does not mean that the disorder is a single-gene trait.

Which term is used to describe the process when a child receives two members of a gene pair, one inherited from the mother and the other from the father? Phenotype Locus Genotype Alleles

Alleles Two members of a gene pair, one inherited from the mother and the other from the father, are called alleles. The genes on each chromosome are arranged in pairs and in strict order, with each gene occupying a specific location or locus. Genotype is the genetic makeup, as distinguished from the physical appearance, of an organism or a group of organisms. Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product.

A sonogram on a woman in the first trimester of her pregnancy shows abnormal fetal findings. The nurse prepares to provide the woman with information concerning which diagnostic procedure? Amniocentesis Chorionic villus sampling Biochemical analysis Percutaneous umbilical cord blood sampling

Amniocentesis The amniocentesis is useful in women with elevated risk on first trimester screen or quad screen; abnormal fetal findings on sonogram; or in parents who are carriers or with a strong family history of an inherited disease. Chorionic villus sampling is an invasive diagnostic procedure that obtains tissue that can be used for fetal chromosome studies, DNA analysis and biochemical studies. Percutaneous umbilical cord blood sampling (PUBS) is used for prenatal diagnosis of hemoglobinopathies, coagulation disorders, metabolic and cytogenetic disorders, and immunodeficiencies. Biochemical analyses can be used to detect abnormal levels of AFP and abnormal biochemical products in the maternal blood and in specimens of amniotic fluid and fetal blood.

A woman gave birth to a small infant with a malformed skull. The infant grows slowly and shows signs of substantial cognitive and intellectual deficits. The child also has facial abnormalities that become more striking as it develops. What might the nurse expect to find in the mother's pregnancy history? Chronic alcohol use Active herpes simplex infection Folic acid deficiency Chronic cocaine use

Chronic alcohol use The infant's signs and symptoms are characteristic of fetal alcohol syndrome. Folic acid deficiency is associated with neural tube defects, such as anencephaly and spina bifida. Cocaine use is associated with some of the same signs and symptoms as alcohol use but does not produce the characteristic facial abnormalities of fetal alcohol syndrome. Herpes simplex infection, although it is associated with microcephaly, hydrocephalus, defects of the eye, and hearing problems, also does not produce characteristic facial abnormalities.

The nurse is preparing to administer a pregnant client's medication when it is noted that the client is prescribed tetracycline for an infection. The nurse should do which of the following? Ask another nurse to confirm the dose/administration Refuse to administer the medication Administer the medication as ordered Contact the physician

Contact the physician

Which disease is caused by a genetic defect of chloride transport? Cystic fibrosis Spherocytosis Phenylketonuria von Willebrand disease

Cystic fibrosis

With increasing age comes a greater chance of a woman having been exposed to damaging environmental agents such as drugs, chemicals, and radiation. These factors may act on the aging oocyte to cause which abnormality in a fetus? Marfan syndrome Turner syndrome Down syndrome Patau syndrome

Down syndrome

Which action is an appropriate intervention by a nurse working with the parents of an infant newly diagnosed with Tay-Sachs disease? Teach the efficacy of a low-protein diet. Teach parents to keep infant's head elevated for 30 minutes after eating. Administer intravenous antibiotics as ordered. Encourage parents to verbalize fears and feelings.

Encourage parents to verbalize fears and feelings.

When the mother of an adolescent with Turner syndrome asks the nurse why the physician is prescribing estrogen therapy, the nurse provides which explanation? To prevent short stature To prevent development of diabetes To promote intellectual development To promote secondary sex characteristics

To promote secondary sex characteristics

Is it true or false that prenatal screening can be used to rule out all possible fetal abnormalities? False True

False

Which risk factor increases the chances of the development of a neural tube defect during embryonic development? Iron deficiency Folate deficiency Calcium deficiency Ascorbic acid deficiency

Folate deficiency

After studying genetic disorders, the pathophysiology student knows that which of the following is true? Sickle cell anemia is caused by multiple gene defects. Few diseases caused by single-gene defects have been identified. Diabetes mellitus is caused by a single-gene defect. Genotype determines phenotype.

Genotype determines phenotype.

A genotype associated with hypertension has been found to have 50% penetrance. What does this mean for the clients chance of developing hypertension? Half of the people with the genotype will have hypertension resulting from this factor. There is a 50% chance that this individual had a parent with hypertension that was genetically based. There is a 50% chance that an individual with this genotype will pass it on to a child. Half of the base pairs in the DNA of this gene are known to correlate with hypertension.

Half of the people with the genotype will have hypertension resulting from this factor. Penetrance represents the ability of a gene to express its function. Fifty percent penetrance means 50% of persons with this specific genotype will have the phenotype in question (hypertension). Penetrance does not denote a percentage chance of inheritance. As well, it does not denote the actual proportion of base pairs that affect the phenotype.

Following routine newborn testing, an infant has been diagnosed with an elevated phenylalanine level. The nurse teaches the parents to follow a strict low-protein diet to prevent which major complication for the infant? Cardiac valvular disorders Impaired brain development Thyroid metabolism errors Kidney failure

Impaired brain development

While teaching a client, the nurse should emphasize which information about an autosomal dominant disorder? It is characterized by affected X transmission to daughters. It has variation in gene penetration and expression. It is characterized by aneuploidy of genes in all cells. It is characterized by deficiencies in enzyme synthesis.

It has variation in gene penetration and expression.

Which health care provider is the highest priority for immediate assistance in the first 24 hours following the birth of a newborn with a cleft lip? lactation consultant respiratory therapist social worker occupational therapist

Lactation consultant Infants with a cleft lip typically have difficulty with feeding, and the assistance of a lactation consultant may be of help in establishing feeding patterns. Oxygenation is not a typical problem, while activities of daily living and assistive devices are not relevant considerations. While social work is often of assistance when a child is born with a congenital condition, a cleft lip has fewer implications than most other inherited disorders.

Which assessment finding supports the diagnosis of Turner syndrome? Intellectual disability Enlarged breasts Early onset puberty Short stature

Short stature

Mendelian inheritance characteristics are most closely associated with which one of the following?

Marfan syndrome Marfan syndrome is an autosomal dominant disorder caused by a mutant allele at a single gene locus and follows Mendelian patterns of inheritance.-Congenital heart disease and diabetes mellitus are multifactorial inheritance disorders.- Turner syndrome is a chromosomal disorder.

A couple is scheduled to obtain familial lineage studies. The nurse is providing education. To which aspect of the DNA analysis should the woman pay particular attention regarding inherited disorders? Mitochondrial DNA Mitochondrial RNA Extrachromosomal DNA G-protein-linked receptors

Mitochondrial DNA

A nurse confers with the attending physician about a client with encephalopathy who has been attributed to mitochondrial gene mutation. Why do mutations of the mitochondria affect the brain? Mitochondrial mutations can affect neural gene expression. Mitochondrial gene products can cross the blood-brain barrier. Mitochondrial mutations affect the ability of tissues to synthesize ATP, and tissues with high demands malfunction without enough ATP. Mitochondria are only active in the brain and silenced in other tissues.

Mitochondrial mutations affect the ability of tissues to synthesize ATP, and tissues with high demands malfunction without enough ATP.

The nurse is teaching a class of pregnant woman about nutrition, emphasizing their need for folic acid. The nurse's rationale for this relates to prevention of which birth defect? Congenital heart defects Attention deficit disorder Blindness Neural tube defects

Neural tube defects

An adolescent presents at the clinic with reports of pedunculated lesions projecting from the skin on the trunk area. The nurse knows that this is a sign of: Klinefelter syndrome Neurofibromatosis type 1 Down syndrome Marfan syndrome

Neurofibromatosis-1 Explanation: In more than 90% of persons with neurofibromatosis-1, cutaneous and subcutaneous neurofibromas develop in late childhood or adolescence. The cutaneous neurofibromas, which vary in number from a few to many hundreds, manifest as soft, pedunculated lesions that project from the skin. Marfan syndrome affects several organ systems, including the ocular system (eyes), the cardiovascular system (heart and blood vessels), and the skeletal system (bones and joints). Down syndrome is a congenital condition characterized by varying degrees of intellectual disability and multiple defects. Klinefelter syndrome is a condition that occurs in men who have an extra X chromosome in most of their cells. The syndrome can affect different stages of physical, language, and social development. The most common symptom is infertility.

A nurse caring for a client with a genetic disorder of mitochondrial DNA assesses for abnormalities in which body system? Neuromuscular Genitourinary Lymphatic Gastrointestinal

Neuromuscular

A client is scheduled for fetal ultrasound. Which type of fetal abnormalities will the nurse teach the client the ultrasound is able to detect? chromosomal defects single-gene disorders metabolic disorders skeletal abnormalities

Skeletal abnormalities

When quizzing obstetrical nursing students regarding tissues affected by mitochondrial DNA mutations, the instructor would accept which response? Select all that apply. Absent testes Retinal degeneration Deafness Cardiac valve abnormalities Palatal abnormalities

Retinal degeneration Deafness

Which health problem may be identified by a TORCH screening test? Rhinovirus and Ormond disease Chlamydia and rickets Rubella and herpes Tenovaginitis and human papillomavirus

Rubella and herpes

Select the screening procedure performed on newborns to decrease the risk of intellectual disability and compromised neurological development. Vitamin K injection Erythromycin eye ointment application Serum glucose test Serum phenylalanine test

Serum phenylalanine test

Select the screening procedure performed on newborns to decrease the risk of intellectual disability and compromised neurological development. Vitamin K injection Serum phenylalanine test Serum glucose test Erythromycin eye ointment application

Serum phenylalanine test

Which symptoms support the diagnosis of the autosomal recessive disorder Tay-Sachs disease? Absence of melanin in the skin, hair, and eyes Red blood cell defect resulting in periods of severe pain Respiratory distress that results of excessive secretions Severe mental deterioration originating in infancy

Severe mental deterioration originating in infancy

After attending a preconception workshop, a young woman asks the educator to explain neural tube defects (NTD). Which conditions are examples of neural tube defects? Select all that apply. Anencephaly Heart defects Spina bifida Cleft palate Encephalocele

Spina bifida Anencephaly- A lethal birth defect in which most of the brain and parts of the skull are missing; absence of the encephalon. Encephalocele- A form of hernia of the brain and its membranes through an opening in the skull.

The health care provider informs the client that she is at risk for developing an autosomal recessive disorder. For which disorder may the client be at risk? Neurofibromatosis type 2 Marfan syndrome Tay-Sachs disease von Recklinghausen disease

Tay-Sachs disease

A person's genotype can best be described as which of the following? Traits that are observable or apparent Traits that are expressed in a dominant pattern Traits that are expressed in a recessive pattern The genetic makeup of an individual

The genetic makeup of an individual

Genetic counseling and prenatal screening are tools both for the parents of a child with a defect and for those couples who want a child but are at high risk for having a child with a genetic problem. What are the objectives of prenatal screening? To detect fetal abnormalities and to provide parents with information needed to make an informed choice about having a child with an abnormality To detect fetal abnormalities and to provide information to the parents on where they can have the pregnancy terminated if they choose to To allow parents at risk for having a child with a specific defect to begin a pregnancy with the assurance that knowledge about the presence or absence of the disorder in the fetus can be confirmed by testing and to provide information on where they can have the pregnancy terminated if they choose to To provide parents with information needed to make an informed choice about having a child with an abnormality and to assure the prospective parents that any defect in their hoped for child can be identified

To detect fetal abnormalities and to provide parents with information needed to make an informed choice about having a child with an abnormality

The pregnant client asks if there are any precautions she should take in caring for the family cat. The nurse explains that she should limit contact with the cat's litter box. The litter box may contain which organism that can cause fetal malformations? Cytomegalovirus Rubella Herpes Toxoplasmosis

Toxoplasmosis

The genetic counselor is explaining structural changes in chromosomes that result from breakage and rearrangement of chromosome parts. The pattern that occurs when there are simultaneous breaks in two chromosomes, from different pairs, with exchange of chromosome parts is: Isochromosome formation Translocation Ring formation Inversion

Translocation

The provider is doing genetic counseling with a client. He explains that which condition affects only females? Fragile X syndrome Turner syndrome Klinefelter syndrome Down syndrome

Turner syndrome

The provider receives fetal karyotype results on one of his clients. The karyotype describes an absence of all or part of the X chromosome. Which condition does the fetus exhibit? Achondroplasia Klinefelter syndrome Down syndrome Turner syndrome

Turner syndrome

While examining a client, the practitioner notices large, flat, cutaneous pigmentations. They are a uniform light brown with sharply demarcated edges. He uses a Wood lamp to better detect the lighter spots. The practitioner knows that the pigmentations may be a component of which disorder? Down syndrome Von Recklinghausen disease Klinefelter syndrome Cystic fibrosis

Von Recklinghausen disease

While examining a client, the practitioner notices large, flat, cutaneous pigmentations. They are a uniform light brown with sharply demarcated edges. He uses a Wood lamp to better detect the lighter spots. The practitioner knows that the pigmentations may be a component of which disorder? Von Recklinghausen disease Down syndrome Cystic fibrosis Klinefelter syndrome

Von Recklinghausen disease

A client goes to radiology for a series of x-rays. As the lead apron is placed over the client, he asks why it is needed. The client should be told that the vest is to protect: against protein breakage. against chromosomal breakage. the cell cytoplasm. against lipid rearrangement.

against chromosomal breakage.

The nurse is explaining congenital defects to a newly pregnant client. She explains that one of the most common birth defects is: congenital heart disease. cleft lip with or without cleft palate. spina bifida. pyloric stenosis.

cleft lip with or without cleft palate.

The nurse is explaining congenital defects to a newly pregnant client. She explains that one of the most common birth defects is: cleft lip with or without cleft palate. pyloric stenosis. spina bifida. congenital heart disease.

cleft lip with or without cleft palate. Explanation: Cleft lip with or without cleft palate is one of the most common birth defects. Other congenital defects that are thought to arise through multifactorial inheritance are clubfoot, congenital dislocation of the hip, congenital heart disease, pyloric stenosis, and urinary tract malformation.

A young man has been diagnosed with Huntington disease following several months of progressive muscle weakness. The man has two young children: one boy and one girl. The nurse should teach the man that: the children have an increased risk of Huntington disease but the risk is unknown because the disease is multifactorial. both children will develop Huntington disease because it is autosomal dominant. each child has 50% chance of developing Huntington disease. the girl will develop Huntington disease after puberty

each child has 50% chance of developing Huntington disease. In a single-gene autosomal dominant disease such as Huntington, the affected parent has a 50% chance of transmitting the disorder to each offspring. Sex-linked differences do not exist.

The most critical time for teratogenic influence in embryonic development is: from day 60 to 90 after conception. from conception to day 15. from day 90 to day 120 after conception. from day 15 to day 60 after conception.

from day 15 to day 60 after conception.

The nurse explains to prospective parents that AA or aa in a Punnett square represent two alleles of a given pair that are the same, or: dominant. homozygotes. recessive. heterozygotes.

homozygotes

The nurse is studying genetic disorders. She learns that an allele is: one of two members of a gene pair, for a particular trait, in a chromosome pair. the physical trait associated with a particular gene. the male or female half of a gene pair. the presence of more than two chromosomes to a set.

one of two members of a gene pair, for a particular trait, in a chromosome pair.

The nurse is studying genetic disorders. She learns that an allele is: one of two members of a gene pair, for a particular trait, in a chromosome pair. the presence of more than two chromosomes to a set. the male or female half of a gene pair. the physical trait associated with a particular gene.

one of two members of a gene pair, for a particular trait, in a chromosome pair.

Teratogenic substances cause abnormalities during embryonic and fetal development. These substances have been divided into three classes. These classes are called: radiation; drugs and chemical substances; and infectious agents. period of organogenesis, third trimester, 2nd trimester. drugs and chemical substances; smoking; bacteria and virus. outside environmental substances, inside environmental substances, internal environmental substances.

radiation; drugs and chemical substances; and infectious agents.

The person's phenotype can best be described as: traits that are expressed in a dominant pattern. traits that are expressed in a recessive pattern. traits that are observable or apparent. the genetic makeup of an individual.

traits that are observable or apparent.

The person's phenotype can best be described as: traits that are expressed in a recessive pattern. traits that are expressed in a dominant pattern. the genetic makeup of an individual. traits that are observable or apparent.

traits that are observable or apparent.