Topic 4 Nursing practice issues/ethics; scope of practice

Question 1

Genetic test

Answer 1

The analysis of DNA, RNA, chromosomes, proteins, and protein metabolites to identify heritable genotypes, mutations, phenotypes, or karyotypes.

Question 2

A mutation in the _ gene causes cystic fibrosis.

Answer 2

CFTR.

Question 3

The most up-to-date information about the availability of genetic testing can be found at _

Answer 3

genetests.org

Question 4

Marfan syndrome inheritance is _

Answer 4

Autosomal dominant.

Question 5

Diagnostic test

Answer 5

1. A test done to confirm or refute a particular diagnosis in a symptomatic person.
2. Provides information about other family members as well as the person being tested.

Question 6

Predictive test

Answer 6

A genetic test designed for asymptomatic persons wanting to know about their risk of getting a genetic disease in the future.

Question 7

Genetic screening vs. testing

Answer 7

1. Screening = Testing on a population basis to identify individuals at risk for developing or transmitting a specific disorder (have a higher tolerance for false positive/negatives because there is follow-up testing).
2. Testing = Testing of individuals based on family history of a disorder; precision of the test is more important.

Question 8

Direct testing examines _

Answer 8

The DNA or RNA that makes up a gene.

Question 9

Biochemical testing examines _

Answer 9

Genetic metabolites.

Question 10

Cytogenetic testing examines _

Answer 10

The chromosomes.

Question 11

Detecting carrier status

Answer 11

Can only be done through direct testing; biochemical testing would not be useful because the person will not have altered metabolites.

Question 12

While DNA can be tested directly for most genetic disorders, sometimes it is more cost-effective to run a _

Answer 12

Biochemical test.

Question 13

Three disorders that are diagnosed through biochemical testing

Answer 13

1. Cystic fibrosis - chloride sweat test (high).
2. PKU: blood phenylalanine levels (high).
3. Tay-Sachs: blood hexosaminidase A levels (low).

Question 14

_ genetic testing is key to advance personalized medicine/nursing.

Answer 14

Predictive.

Question 15

Steps in predictive testing

Answer 15

1. The diagnosis of a genetic condition is confirmed in the family before predictive testing is used.
2. Confirm the diagnosis in an affected relative first; test for mutation.
3. Then offer predictive testing to other relatives at risk.

Question 16

Presymptomatic vs. predisposition testing

Answer 16

1. Presymptomatic - e.g., Huntington’s; if the mutation is present, the person will develop the disease.
2. Predisposition - e.g., BRCA and breast cancer; the mutation predisposes a person to breast cancer, but development of the disease is not certain.

Question 17

Beneficence

Answer 17

Duty to make decisions based on what is considered “good” or of the most benefit to others.

Question 18

Nonmaleficence

Answer 18

Duty to do no harm.

Question 19

Autonomy

Answer 19

Duty to respect a person’s right to make their own decisions.

Question 20

Veracity

Answer 20

Duty to tell the truth.

Question 21

Fidelity

Answer 21

Duty to keep one’s promise or word.

Question 22

Justice

Answer 22

Duty to be fair in the distribution of risks and benefits.

Question 23

Confidentiality

Answer 23

Duty to hold information as private.

Question 24

Genetic Information Nondiscrimination Act (GINA)

Answer 24

1. Federal law that prohibits discrimination on the basis of genetic information - affects health insurers and employers, not health care practitioners.
2. Family medical history, carrier testing, prenatal genetic testing, susceptibility testing, analysis of tumors, and other genetic testing are protected information.
3. Insurers cannot require someone to undergo a genetic test, cannot use the results of genetic tests in setting a person’s premium, and cannot treat genetic information as a pre-existing condition.
4. Employers cannot request or require an employee to undergo genetic testing and cannot use genetic information in employment decisions (hiring, firing, promotions, etc.).
5. Exceptions: Does not apply to life insurers, does not apply to employment organizations with fewer than 15 employees, does not apply to military and federal employees.

Question 25

Disclosure of ordinarily confidential genetic information to family members - exceptional circumstances

Answer 25

Disclosure is permissible when:

1. Attempts for the patient to disclose have failed.
2. Harm is serious and likely to occur; disease is identifiable; standards of care indicate early monitoring or care will reduce risks.
3. Harm from failure to disclose should outweigh the harm from disclosure.

Question 26

Cells that can be used for DNA testing

Answer 26

Any tissue with a true nucleus, such as nasal epithelial cells, can provide DNA for genetic testing. The distal ends of hair shafts do not contain cells with a nucleus, only the hair root does. Mature red blood cells have no nucleus (and no mitochondria).

Question 27

Genetic testing of an asymptomatic woman whose sister is positive for the mutation that is responsible for autosomal dominant disorder that has a 70% penetrance rate would fall into which testing category?

Answer 27

Predictive predisposition. [The test is predictive rather than diagnostic because the woman does not have any symptoms of the disorder. So, the test is not being performed to confirm or rule out a disorder diagnosis. The test is also considered “predisposition” testing rather than “presymptomatic” testing because the disorder has a 70% penetrance rate. This means that even if the woman is positive, she has a 30% chance of never developing symptoms but has a genetic predisposition to the disorder.]

Question 28

Polymerase chain reaction (PCR)

Answer 28

Precisely expands or amplifies a specific segment of DNA so that more of it is available for testing. PCR itself does not test the DNA directly for anything, cannot itself determine whether DNA or a gene is paternal or maternal, and does not preserve specimens.

Question 29

What is the major disadvantage to the fluorescence in situ hybridization (FISH) method of genetic testing?

Answer 29

Single nucleotide mutations cannot be detected. [FISH examines portions of chromosomes, not the sequence of individual nucleotides. FISH can be performed on preserved tissue as well as living tissue specimens. It is an accurate test with great specificity and a low risk for either false positives or false negatives.]

Question 30

When is fluorescence in situ hybridization (FISH) most likely to be used?

Answer 30

To determine whether a stillborn infant has trisomy 13. [FISH is often used to identify chromosomal variations in number or structure and to identify deletions or duplications. The goal is to determine the presence or absence of a chromosomal type of genetic variation.]

Question 31

A patient is 34 years old and concerned about possibly being a carrier for HNPCC because his father died of colon cancer at 39, his father’s sister died of colon cancer at age 41, and his brother (aged 37) now has colon cancer. The brother’s testing is negative for all the known mutations associated with inherited forms of colon cancer. How should this patient be counseled about his risk for colon cancer?

Answer 31

Explain that testing for him would be of no benefit because of the current test limitations but that his family history does place him a high risk. [Further testing for common mutations would be of no benefit to this patient. His risk is not known but should be considered high on the basis of family history.]

Question 32

Advanced Practice Nurse in Genetics (APNG)

Answer 32

1. No certification exam - professional portfolio review process.
2. Requires 300 hours of genetic practicum experiences as a clinical genetic nurse and completion of a log of 50 cases within 5 years of the application.
3. Must be a graduate of an accredited graduate program in nursing.

Question 33

Your patient, Maggie, insists that her mother have genetic testing to determine if her breast cancer is connected to a mutation in the BRCA1/2 genes. Maggie is concerned about her own risk for getting breast cancer and that of her children, but Maggie’s mom does not want to be tested. What ethical principle is one of several that must be considered in evaluating this case?

Answer 33

Maggie’s mother’s “right to privacy.” [Maggie’s mother has a right to keep her genetic information private even though Maggie would like to know if her mother carries a BRCA1/2 mutation.]

Question 34

Sometimes health-care providers with information about family members’ genetic risk are confronted by conflicting ethical principles. Which principle is LEAST likely to conflict with the health-care provider’s “duty to warn”?

Answer 34

Genetic discrimination. [The ethical principles of “right to privacy,” “autonomy,” and “beneficence” can all conflict with the health-care provider’s duty to warn. If we support a patient’s wishes not to share their genetic information with their family members we are respecting their “right to privacy” and “autonomy.” What is “good” for the patient (respecting the right to privacy) may conflict with what is “good” for the family members (being warned). This creates a problem respecting beneficence. Genetic discrimination is a social problem but not an ethical principle.]