ch8 prepU Genetics

A nurse is obtaining health history from a client with a genetic disorder. Which of the following would be most appropriate for the nurse to establish the pattern of inheritance?

Construct a pedigree of the client's family.

A patient has an autosomal recessive inherited condition. For what type of disorder does the nurse anticipate the patient will be treated?

Cystic fibrosis

A nurse is working with a couple who will be undergoing genetic testing. Which of the following would the nurse prepare the couple for as the first genetic test?

Family history

A nurse assessing a client's genetic risk for a particular disease uses a pedigree chart for visual aid. What is a benefit of the pedigree chart?

It may motivate a client in health-promoting behaviors.

Which condition is tested for as a part of normal newborn screening?

Phenylketonuria Testing for phenylketonuria is part of normal newborn screening. Prenatal screening includes testing for Down syndrome. Preconception screening includes testing for sickle cell anemia and cystic fibrosis.

A newborn infant's mother requests more information on how the infant has red hair when only a "few" individuals in the family has this trait. What term does the nurse understand the client is speaking about?

Phenotype

While assessing a client, the nurse notes that the client has numerous freckles on his skin. The nurse interprets this finding as which of the following?

Phenotype Phenotype refers to the person's entire physical, biochemical, and physiologic makeup as determined by the person's genotype and environmental factors. Thus, the client's freckles are observable characteristics of his genotype, his unique genetic makeup including his genes, and any variations therein. Genome refers to the entire genetic complement of an individual genotype. Variable expression refers to the charateristic indicating the degree of severity of a condition.

The nurse working in the labor and delivery unit prepares to test for which condition as a part normal newborn screening?

Phenylketonuria

A female client is a carrier for a gene mutation on one of her X chromosomes. Her spouse is unaffected. The nurse understands that which of the following is most likely?

The client's sons have a 50% chance of being affected.

A nurse is obtaining a genetic family history of a client. The nurse collects information about family members going back at least how many generations?

3

A 32-year-old patient has just been told that she has the BRCA1 hereditary breast cancer gene mutation. What is her risk of developing cancer by the age of 65 years?

80% Another phenomenon observed in autosomal dominant inheritance is penetrance, or the percentage of persons known to have a particular gene mutation who actually show the trait. Almost complete penetrance is observed in conditions such as achondroplasia, in which nearly 100% of people with the gene mutation typically display traits of the disease. However, in some conditions, the presence of a gene mutation does not invariably mean that a person has or will develop an autosomal inherited condition. For example, a woman who has the BRCA1 hereditary breast cancer gene mutation has a lifetime risk of breast cancer that can be as high as 80%, not 100%. This quality, known as incomplete penetrance, indicates the probability that a given gene will produce disease.

What target cultural population is a priority for the nurse to educate about prevention of hypertension?

African Americans

A nurse is reviewing the medical record of a patient who has just learned that she is pregnant. Which of the following would the nurse identify as being least likely to indicate a need for a genetic evaluation referral?

Age 33 years at expected delivery

The nurse is reading the chart of a new client at the genetics clinic. The chart notes that the client, her brother, and her mother all have inherited a particular condition. The nurse plans care for a condition with which type of inheritance pattern?

Autosomal dominant An individual who has an autosomal dominant inherited condition carries a gene mutation for that condition on one chromosome of a pair. The pattern of inheritance in autosomal recessive inherited conditions is different from that of autosomal dominant inherited conditions in that it is more horizontal than vertical, with relatives of a single generation tending to have the condition. Chromosome X-linked conditions may be inherited in families in recessive or dominant patterns. In both patterns, the gene mutation is located on the X chromosome. All males inherit an X chromosome from their mother with no counterpart; hence, all males express the gene mutation. Neural tube defects, such as spina bifida and anencephaly, are examples of multifactorial genetic conditions. The majority of neural tube defects are caused by both genetic and environmental influences that combine during early embryonic development and lead to incomplete closure of the neural tube.

Cystic fibrosis is a condition passed on through which type of inheritance?

Autosomal recessive

A nurse working as part of a genetics counseling team is preparing a presentation for a career day discussion at a local college of nursing. When describing the genomic framework for nursing, which of the following would the nurse include as being most important?

Being keenly aware of one's own attitudes and assumptions about genetics and genomics

The nurse is providing client education to a pregnant woman regarding genetic testing for Down syndrome. The nurse determines that the client understands the teaching when the client states that diagnostic testing for Down syndrome includes which test?

Chromosomal analysis

The nurse is working with a 40-year-old pregnant woman about to undergo amniocentesis. The nurse provides appropriate education by stating that amniocentesis is performed for a prenatal diagnosis of which condition?

Cystic fibrosis

Nondisjunction of a chromosome results in which diagnosis?

Down syndrome

A nurse is preparing a patient for genetic testing that will involve a detailed examination of the chromosomes to detect small abnormalities and identify rearrangements. The nurse would be preparing the patient for which of the following?

Fluorescent in situ hybridization (FISH) Fluorescent in situ hybridization (FISH) is useful to detect small abnormalities in chromosomes and to characterize chromosomal rearrangement. DNA analysis may be used for testing for cystic fibrosis and fragile X syndrome. Hexosaminidase A activity testing is used for Tay-Sachs disease. Hemoglobin electrophoresis is used as genetic testing for sickle-cell anemia.

Which of the following is associated in a client with poor metabolism based on a person's CYP genotype and drug response?

Greater risk for toxicity Poor metabolizers may have many adverse effects or toxicities from high blood levels of drugs and thus need a lower dose. Ultrarapid metabolizers have inadequate treatment responses because of the lower drug blood levels and may need a higher dose or more frequent dosing. Intermediate metabolizers have some enzyme acitivity leading to differenes in treatment response.

After completing a history and physical assessment of a client who has just found out that she is pregnant, the nurse determines the need for a referral for a genetic evaluation based on which of the following? Select all that apply.

History of diabetes Brother with intellectual disability Two previous unexplained miscarriages

Students are reviewing information about genetic tests and associated conditions. They demonstrate understanding of this information when they identify which conditions as being identified by DNA analysis? Select all that apply.

Huntington disease Cystic fibrosis Fragile X syndrome

After teaching nursing students about autosomal-dominant and autosomal-recessive inherited disorders, the instructor determines that the teaching was successful when the class identifies which of the following as true about autosomal-dominant inherited conditions?

Males and females are equally affected by this pattern of inheritance.

A nurse is preparing a presentation for a community health fair about genetics and genetic disorders. Which of the following would the nurse be least likely to integrate into the presentation?

Most genetic disorders occur because of specific yet simple inheritance patterns.

The nurse is reviewing the chart of a client who was diagnosed with a cleft lip and palate at birth. The nurse demonstrates understanding of this disorder, identifying it as involving which type of inheritance pattern?

Multifactorial Cleft lip and palate are considered multifactorial genetic conditions, resulting from the interactions of multiple gene mutations and environmental influences. Huntington disease, Marfan syndrome, and neurofibromatosis are examples of autosomal-dominant genetic conditions. Cystic fibrosis, sickle-cell anemia and phenylketonuria are examples of autosomal-recessive genetic conditions. Duchenne muscular dystrophy, hemophilia A and B, and certain forms of color blindness are examples of X-linked recessive genetic conditions.

A client's history reveals evidence of a trisomy. The nurse interprets this as resulting from which of the following?

Nondisjunction With a trisomy, a pair of chromosomes has failed to separate completely, creating a sperm or oocyte that contains three copies of a specific chromosome. This is called nondisjunction. Mutation refers to changes in the structure of the gene that permanently changes the sequence of DNA. Deletion is a type of mutation that results from the loss of a gene. Translocation is a type of mutation that occurs when the longer DNA segment is rearranged.

"What is a characteristic of the genomic era of personalized medicine's impact on health care?"

Optimization of risk reduction related to genetic predisposition

Which is the first step in establishing a pattern of inheritance?

Pedigree

After assessing a client's family history, the nurse determines the need for a genetic referral based on which of the following?

Several relatives diagnosed with colon cancer

Which genetic condition is caused by a small gene mutation that affects protein structure, producing hemoglobin S?

Sickle cell anemia

A nurse is assessing a couple of Ashkenazi Jewish descent. The nurse understands that carrier testing for which condition would be least appropriate for this couple?

Sickle-cell disease People of African-American descent are routinely offered carrier testing for sickle-cell anemia. People of Ashkenzai Jewish descent should be offered carrier testing for Tay-Sachs disease, Canavan disease, and cystic fibrosis.

A child is diagnosed with Turner syndrome. When describing this genetic condition to the parents, which of the following would the nurse include?

The child will have fertility problems. Turner's syndrome is characterized by girls who have a single X chromosome, causing short stature and infertility.

A patient has been identified as a poor metabolizer for a drug that undergoes CYP 450 metabolism. The nurse interprets this information as indicating which of the following?

The patient is at increased risk for toxicity. Poor metabolizers have a specific single nucleotide polymorphism (SNP) variation in a CYP gene that causes little or no enzyme function, resulting in very little or no drug metabolism and higher levels of active drug because the drug cannot be absorbed or excreted. Poor metabolizers may have adverse effects or toxicities from high blood levels of drugs and need a lower dose.

The nurse is conducting a community education class on genetics and genomics. The nurse explains that a chromosomal difference that involves an extra or missing chromosome is known as

aneuploidy. Aneuploidy involves an extra or missing chromosome, and always causes associated intellectual or physical disability to some degree. Haploid refers to eggs and sperm because they contain a single copy, rather than the usual two copies, of each chromosome. Monosomy occurs when one chromosome pair is missing from normally diploid cells. Trisomy is the presence of one extra chromosome in an otherwise diploid chromosome complement.

The nurse is conducting an educational program for unlicensed personnel on the Health Insurance Portability and Accountability Act (HIPAA) of 1996. The nurse determines that the unlicensed personnel understand HIPAA when they state that it prohibits

the use of genetic information to establish insurance eligibility.