Ch. 4 Genetics

3. A patient with a family history of cystic fibrosis (CF) asks for information about genetic testing. Which response by the nurse is most appropriate? a.Refer the patient to a qualified genetic counselor. b.Ask the patient why genetic testing is so important. c.Remind the patient that genetic testing has many social implications. d.Tell the patient that cystic fibrosis is an autosomal recessive disorder.

A A genetic counselor is best qualified to address the multiple issues involved in genetic testing for a patient who is considering having children. Although genetic testing does have social implications, the woman will be better served by a genetic counselor who will have more expertise in this area. CF is an autosomal recessive disorder, but the patient might not understand the implications of this statement. Asking why the patient feels genetic testing is important may imply to the patient that the nurse is questioning her value system.

4. A nurse obtains health histories when admitting clients to a medical-surgical unit. With which client should the nurse discuss predisposition genetic testing? a. Middle-aged woman whose mother died at age 48 of breast cancer b. Young man who has all the symptoms of rheumatoid arthritis c. Pregnant woman whose father has sickle cell disease d. Middle-aged man of Eastern European Jewish ancestry

A A client with a family history of breast cancer should be provided information about predisposition testing. Predisposition testing should be discussed with clients who are at high risk of hereditary breast, ovarian, and colorectal cancers so that the client can engage in heightened screening activities or interventions that reduce risk. The client with symptoms of rheumatoid arthritis should be given information about symptomatic diagnostic testing. The client with a familial history of sickle cell disease and the client who is of Eastern European Jewish ancestry should be given information about carrier genetic testing.

11. A nurse cares for a pregnant client who has a family history of sickle cell disease. The client is unsure if she wants to participate in genetic testing. What action should the nurse take? a. Provide information about the risks and benefits of genetic testing. b. Empathize with the client and share a personal story about a hereditary disorder. c. Teach the client that early detection can minimize transmission to the fetus. d. Advocate for the client and her baby by encouraging genetic testing.

A Genetic counseling is to be nondirective. The nurse should provide as much information as possible about the risks and benefits but should not influence the clients decision to test or not test. Once the client has made a decision, the nurse should support the client in that decision. Carrier testing will determine if a client without symptoms has an allele for a recessive disorder that could be transmitted to his or her child. Genetic testing will not minimize transmission of the disorder.

1. The sister of a patient diagnosed with BRCA generelated breast cancer asks the nurse, Do you think I should be tested for the gene? Which response by the nurse is most appropriate? a. In most cases, breast cancer is not caused by the BRCA gene. b. It depends on how you will feel if the test is positive for the BRCA gene. c. There are many things to consider before deciding to have genetic testing. d. You should decide first whether you are willing to have a bilateral mastectomy.

C Although presymptomatic testing for genetic disorders allows patients to take action (such as mastectomy) to prevent the development of some genetically caused disorders, patients also need to consider that test results in their medical record may affect insurance, employability, etc. Telling a patient that a decision about mastectomy should be made before testing implies that the nurse has made a judgment about what the patient should do if the test is positive. Although the patient may need to think about her reaction if the test is positive, other issues (e.g., insurance) also should be considered. Although most breast cancers are not related to BRCA gene mutations, the patient with a BRCA gene mutation has a markedly increased risk for breast cancer.

2. A nurse completes pedigree charts for clients at a community health center. Which diagnosis should the nurse refer for carrier genetic testing? (Select all that apply.) a. Huntington disease b. Breast cancer c. Hemophilia d. Colorectal cancer e. Sickle cell disease f. Cystic fibrosis

C, E, F Of the disease processes listed, the ones that would make the client a candidate for carrier genetic testing would be hemophilia, sickle cell disease, and cystic fibrosis. Although Huntington disease, breast cancer, and colorectal cancer all have genetic components, there is no evidence that carrier genetic testing would be beneficial in diseases such as these.

4. A male patient with hemophilia asks the nurse if his children will be hemophiliacs. Which response by the nurse is appropriate? a.All of your children will be at risk for hemophilia. b.Hemophilia is a multifactorial inherited condition. c.Only your male children are at risk for hemophilia. d.Your female children will be carriers for hemophilia.

D Because hemophilia is caused by a mutation of the X chromosome, all female children of a man with hemophilia are carriers of the disorder and can transmit the mutated gene to their offspring. Sons of a man with hemophilia will not have the disorder. Hemophilia is caused by a single genetic mutation and is not a multifactorial inherited condition.

5. A client who tests positive for a mutation in the BRCA1 gene allele asks a nurse to be present when she discloses this information to her adult daughter. How should the nurse respond? a. I will request a genetic counselor who is more qualified to be present for this conversation. b. The test results can be confusing; I will help you interpret them for your daughter. c. Are you sure you want to share this information with your daughter, who may not test positive for this gene mutation? d. This conversation may be difficult for both of you; I will be there to provide support.

D A nurse should provide emotional support while the client tells her daughter the information she has learned about the test results. The nurse should not interpret the results or counsel the client or her daughter. The nurse should refer the client for counseling or support, if necessary.

6. A patient tells the nurse, I would like to use a home genetic test to see if I will develop breast cancer. Which response by the nurse is best? a. Home genetic testing is very expensive. b. Are you concerned about developing breast cancer? c. Won't you be depressed if the testing shows a positive result? d. Genetic testing can only determine if you are at a higher risk for breast cancer.

B This response uses the communication technique of clarifying to further assess the patients concerns. The other options accurately indicate information about genetic testing, but the initial response by the nurse should be focused on assessment.

3. A nurse teaches clients about patterns of inheritance for genetic disorders among adults. Which disorders have an autosomal dominant pattern of inheritance? (Select all that apply.) a. Breast cancer b. Alzheimers disease c. Hemophilia d. Huntington disease e. Marfan syndrome f. Cystic fibrosis

A, D, E Breast cancer, Huntington disease, and Marfan syndrome have an autosomal dominant pattern of inheritance. Alzheimers disease is a complex disorder with familial clustering, hemophilia is a sex-linked recessive disorder, and cystic fibrosis has an autosomal recessive pattern of inheritance.

2. When counseling a couple in which the man has an autosomal recessive disorder and the woman has no gene for the disorder, the nurse uses Punnett squares to show the couple the probability of their having a child with the disorder. Which statement by the nurse is most appropriate? a. You should consider adoption. b. Your children will be carriers of the disorder. c. Your female children will display characteristics of the disorder. d. Your first-born child will likely display characteristics of the disorder.

B When one parent has an autosomal recessive disorder and the other parent has no genes for the autosomal recessive disorder, the children will not display characteristics of the disorder. However, the children will be carriers of the autosomal recessive disorder.

6. A nurse consults a genetic counselor for a client whose mother has Huntington disease and is considering genetic testing. The client states, I know I want this test. Why do I need to see a counselor? How should the nurse respond? a. The advanced practice nurse will advise you on whether you should have children or adopt. b. Genetic testing can be a stressful experience. Counseling can provide support and education throughout the process. c. There is no cure for this disease. The counselor will determine if there is any benefit to genetic testing. d. Genetic testing is expensive. The counselor will advocate for you and help you obtain financial support.

B Genetic testing is a stressful experience, and clients should be provided with support, education, and assistance with coping. Genetic testing should be performed only after genetic counseling has occurred. The client has the right to decide whether to have children or to participate in genetic testing. Nursing staff should provide both benefits and risks to genetic testing so that the client can make an informed decision. Financial support is not part of genetic counseling.

7. The nurse in the outpatient clinic has obtained health histories for these new patients. Which patient may need referral for genetic testing? a.35-year-old patient whose maternal grandparents died after strokes at ages 90 and 96 b.18-year-old patient with a positive pregnancy test whose first child has cerebral palsy c.34-year-old patient who has a sibling with newly diagnosed polycystic kidney disease d.50-year-old patient with a history of cigarette smoking who is complaining of dyspnea

C The adult form of polycystic kidney disease is an autosomal dominant disorder and frequently it is asymptomatic until the patient is older. Presymptomatic testing will give the patient information that will be useful in guiding lifestyle and childbearing choices. The other patients do not have any indication of genetic disorders or need for genetic testing.

12. A nurse cares for a client who recently completed genetic testing and received a negative result. The client states, I feel guilty because so many of my family members are carriers of this disease and I am not. How should the nurse respond? a. You are not genetically predisposed for this disease but you could still become ill. Lets discuss a plan for prevention. b. Since many of your family members are carriers, you should undergo further testing to verify the results are accurate. c. We usually encourage clients to participate in counseling after receiving test results. Can I arrange this for you? d. It is normal to feel this way. I think you should share this news with your family so that they can support you.

C Clients who have negative genetic test results need counseling and support. Some clients may have an unrealistic view of what a negative result means for their general health. Others may feel guilty that they were spared when some family members were not. The client will not be symptomatic if he is not a carrier of the disease. A second round of testing is not recommended, because false-negatives are rare with this type of testing. It is the clients choice to reveal test results to family members; the nurse should not encourage him to do this.

2. A client is typed and crossmatched for a unit of blood. Which statement by the nurse indicates a need for further genetic education? a. Blood type is formed from three gene alleles: A, B, and O. b. Each blood type allele is inherited from the mother or the father. c. If the clients blood type is AB, then the client is homozygous for that trait. d. If the client has a dominant and a recessive blood type allele, only the dominant will be expressed.

C There are three possible gene alleles: A, B, and O. Blood type is determined by only two of the three specific gene alleles. The blood type OO is homozygous in contrast to the blood type AB, which is heterozygous. In the blood type AO, the gene allele A is dominant and will be expressed as blood type A. It is true that each blood type allele is inherited from the mother or the father.

5. When caring for a young adult patient who has abnormalities in the cytochrome P450 (CYP 450) gene, which action will the nurse include in the patients plan of care? a. Teach that some medications may not work as effectively. b. Teach about genetic risk for cystic fibrosis in any children. c. Suggest that the patient make heart healthy lifestyle choices. d. Discuss the need for screening mammograms starting at age 30.

A The CYP 450 gene affects the metabolism of many medications, and they may not work as effectively or may have unexpected toxic effects. The CYP 450 gene does not affect risk for breast cancer, cystic fibrosis, or coronary artery disease.

7. A health care provider prescribes genetic testing for a client who has a family history of colorectal cancer. Which action should the nurse take before scheduling the client for the procedure? a. Confirm that informed consent was obtained and placed on the clients chart. b. Provide genetic counseling to the client and the clients family members. c. Assess if the client is prepared for the risk of psychological side effects. d. Respect the clients right not to share the results of the genetic test.

A Informed consent is required before genetic testing. The person tested is the one who gives consent. An advanced practice provider should explain the procedure and provide genetic counseling. Although the client should be prepared for the risk of psychological side effects and the clients rights should be respected, the procedure cannot occur without informed consent.

1. A nurse cares for a client who recently completed genetic testing that revealed that she has a BRCA1 gene mutation. Which actions should the nurse take next? (Select all that apply.) a. Discuss potential risks for other members of her family. b. Assist the client to make a plan for prevention and risk reduction. c. Disclose the information to the medical insurance company. d. Recommend the client complete weekly breast self-examinations. e. Assess the clients response to the test results. f. Encourage support by sharing the results with family members.

A, B, E The medical-surgical nurse can assess the clients response to the test results, discuss potential risks for other family members, encourage genetic counseling, and assist the client to make a plan for prevention, risk reduction, and early detection. For some positive genetic test results, such as having a BRCA1 gene mutation, the risk for developing breast cancer is high but is not a certainty. Because the risk is high, the client should have a plan for prevention and risk reduction. One form of prevention is early detection. Breast self-examinations may be helpful when performed monthly, but those performed every week may not be useful, especially around the time of menses. A client who tests positive for a BRCA1 mutation should have at least yearly mammograms and ovarian ultrasounds to detect cancer at an early stage, when it is more easily cured. Owing to confidentiality, the nurse would never reveal any information about a client to an insurance company or family members without the clients permission.

1. A nurse is educating a client about genetic screening. The client asks why red-green color blindness, an X-linked recessive disorder noted in some of her family members, is expressed more frequently in males than females. How should the nurse respond? a. Females have a decreased penetrance rate for this gene mutation and are therefore less likely to express the trait. b. Females have two X chromosomes and one is always inactive. This inactivity decreases the effect of the gene. c. The incidence of X-linked recessive disorders is higher in males because they do not have a second X chromosome to balance expression of the gene. d. Males have only one X chromosome, which allows the X-linked recessive disorder to be transmitted from father to son.

C Because the number of X chromosomes in males and females is not the same (1:2), the number of X-linked chromosome genes in the two genders is also unequal. Males have only one X chromosome, a condition called hemizygosity, for any gene on the X chromosome. As a result, X-linked recessive genes have a dominant expressive pattern of inheritance in males and a recessive expressive pattern of inheritance in females. This difference in expression occurs because males do not have a second X chromosome to balance the expression of any recessive gene on the first X chromosome. It is incorrect to say that one X chromosome of a pair is always inactive in females, or that females have a decreased penetrance rate for this gene mutation. X-linked recessive disorders cannot be transmitted from father to son, but the trait is transmitted from father to all daughters who will be carriers.

10. A nurse cares for a client who has a specific mutation in the a1AT (alpha1-antitrypsin) gene. Which action should the nurse take? a. Teach the client to perform monthly breast self-examinations and schedule an annual mammogram. b. Support the client when she shares test results and encourages family members to be screened for cancer. c. Advise the client to limit exposure to secondhand smoke and other respiratory irritants. d. Obtain a complete health history to identify other genetic problems associated with this gene mutation.

C The a1AT gene mutation increases risk for developing early-onset emphysema. Clients should be advised to limit exposure to smoke and other respiratory irritants as a means of decreasing environmental influences that may aggravate an early onset of emphysema. This gene mutation does not promote cancer, nor does it occur with other identified genetic problems. The BRCA1 gene mutation gives the client a higher risk for developing breast cancer.

9. A nurse cares for a client who has a genetic mutation that increases the risk for colon cancer. The client states that he does not want any family to know about this result. How should the nurse respond? a. It is required by law that you inform your siblings and children about this result so that they also can be tested and monitored for colon cancer. b. It is not necessary to tell your siblings because they are adults, but you should tell your children so that they can be tested before they decide to have children of their own. c. It is not required that you tell anyone about this result. However, your siblings and children may also be at risk for colon cancer and this information might help them. d. It is your decision to determine with whom, if anyone, you discuss this test result. However, you may be held liable if you withhold this information and a family member gets colon cancer.

C This situation represents an ethical dilemma. It is the clients decision whether to disclose the information. However, the information can affect others in the clients family. The law does not require the client to tell family members about the results, nor can the client be held liable for not telling them. The nurse may consider it ethically correct for the client to tell family members so that they can take action to prevent the development of cancer, but the nurse must respect the clients decision.

8. A nurse cares for an adult client who has received genetic testing. The clients mother asks to receive the results of her daughters genetic tests. Which action should the nurse take? a. Obtain a signed consent from the client allowing test results to be released to the mother. b. Invite the mother and other family members to participate in genetic counseling with the client. c. Encourage the mother to undergo genetic testing to determine if she has the same risks as her child. d. Direct the mother to speak with the client and support the clients decision to share or not share the results.

D All conversations and test results must be kept confidential. The client has the right to determine who may be involved in discussions related to diagnosis and genetic testing, who may participate in genetic counseling with the client, and what information may be disclosed to family members. It is the nurses responsibility to provide a private environment for discussions and protect the clients information from improper disclosure. The nurse should support the clients right to disclose or not disclose information.

3. A nurse cares for a client of Asian descent who is prescribed warfarin (Coumadin). What action should the nurse perform first? a. Schedule an international normalized ratio (INR) test to be completed each day. b. Initiate fall precautions and strict activity limitations. c. Teach the client about bleeding precautions, including frequent checks for any bruising. d. Confirm the prescription starts warfarin at a lower-than-normal dose.

D Most individuals of Asian heritage have a single nucleotide polymorphism in the CYP2C19 gene that results in low activity of the enzyme produced. This mutation greatly reduces the metabolism of warfarin, leading to increased bleeding risks and other serious side effects. Any person of Asian heritage who needs anticoagulation therapy should be started on very low dosages of warfarin and should have his or her INR monitored more frequently. The nurse can always teach about the risk of bleeding and can monitor for any bruising. The priority action is for the nurse to check the prescription and confirm the dose prior to administering the medication. It is not necessary to initiate fall precautions and to limit activity based on the administration of warfarin.