NCLEX – Genetics Exam Practice Questions
and Answers Verified by Expert
A father and mother are carriers of phenylketonuria (PKU). Their 2-year-old daughter has PKU. The
couple tells the nurse that they are planning to have a second baby. Because their daughter has PKU,
they are sure that their next baby won’t be affected. What response by the nurse is most accurate?
a. Good planning; you need to take advantage of the odds in your favor.
b. I think you’d better check with your doctor first.
c. You are both carriers, so each baby has a 25% chance of being affected.
d. The ultrasound indicates a boy, and boys are not affected by PKU. - Answer ANS: C - The chance is one
in four that each child produced by this couple will be affected by PKU disorder. This couple still has an
increased likelihood of having a child with PKU. Having one child already with PKU does not guarantee
that they will not have another. These parents need to discuss their options with their physician.
However, an opportune time has presented itself for the couple to receive correct teaching about
inherited genetic risks. No correlation exists between gender and inheritance of the disorder because
PKU is an autosomal recessive disorder.
The nurse is providing genetic counseling for an expectant couple who already have a child with trisomy
18. The nurse should:
a. Tell the couple they need to have an abortion within 2 to 3 weeks.
b. Explain that the fetus has a 50% chance of having the disorder.
c. Discuss options with the couple, including amniocentesis to determine whether the fetus is affected.
d. Refer the couple to a psychologist for emotional support. - Answer ANS: C - Genetic testing, including
amniocentesis, would need to be performed to determine whether the fetus is affected. The couple
should be given information about the likelihood of having another baby with this disorder so that they
can make an informed decision. A genetic counselor is the best source for determining genetic
probability ratios. The couple eventually may need emotional support, but the status of the pregnancy
must be determined first.
The nurse is assessing the knowledge of new parents with a child born with maple syrup urine disease
(MSUD). This is an autosomal recessive inherited disorder, which means that:
, a. Both genes of a pair must be abnormal for the disorder to be expressed.
b. Only one copy of the abnormal gene is required for the disorder to be expressed.
c. The disorder occurs in males and heterozygous females.
d. The disorder is carried on the X chromosome. - Answer ANS: A - MSUD is a type of autosomal
recessive inheritance disorder in which both genes of a pair must be abnormal for the disorder to be
expressed. MSUD is not an X-linked dominant or recessive disorder or an autosomal dominant
inheritance disorder.
In presenting to obstetric nurses interested in genetics, the genetic nurse identifies the primary risk(s)
associated with genetic testing as:
a. Anxiety and altered family relationships.
b. Denial of insurance benefits.
c. High false-positive results associated with genetic testing.
d. Ethnic and socioeconomic disparity associated with genetic testing. - Answer ANS: B - Decisions about
genetic testing are shaped by socioeconomic status and the ability to pay for the testing. Some types of
genetic testing are expensive and are not covered by insurance benefits. Anxiety and altered family
relationships, high false-positive results, and ethnic and socioeconomic disparity are factors that may be
difficulties associated with genetic testing, but they are not risks associated with testing.
A mans wife is pregnant for the third time. One child was born with cystic fibrosis, and the other child is
healthy. The man wonders what the chance is that this child will have cystic fibrosis. This type of testing
is known as:
a. Occurrence risk.
c. Predictive testing.
b. Recurrence risk.
d. Predisposition testing. - Answer ANS: B - The couple already has a child with a genetic disease so they
will be given a recurrence risk test. If a couple has not yet had children but are known to be at risk for
having children with a genetic disease, they are given an occurrence risk test. Predictive testing is used
to clarify the genetic status of an asymptomatic family member. Predisposition testing differs from
presymptomatic testing in that a positive result does not indicate 100% risk of a condition developing.
A key finding from the Human Genome Project is:
and Answers Verified by Expert
A father and mother are carriers of phenylketonuria (PKU). Their 2-year-old daughter has PKU. The
couple tells the nurse that they are planning to have a second baby. Because their daughter has PKU,
they are sure that their next baby won’t be affected. What response by the nurse is most accurate?
a. Good planning; you need to take advantage of the odds in your favor.
b. I think you’d better check with your doctor first.
c. You are both carriers, so each baby has a 25% chance of being affected.
d. The ultrasound indicates a boy, and boys are not affected by PKU. - Answer ANS: C - The chance is one
in four that each child produced by this couple will be affected by PKU disorder. This couple still has an
increased likelihood of having a child with PKU. Having one child already with PKU does not guarantee
that they will not have another. These parents need to discuss their options with their physician.
However, an opportune time has presented itself for the couple to receive correct teaching about
inherited genetic risks. No correlation exists between gender and inheritance of the disorder because
PKU is an autosomal recessive disorder.
The nurse is providing genetic counseling for an expectant couple who already have a child with trisomy
18. The nurse should:
a. Tell the couple they need to have an abortion within 2 to 3 weeks.
b. Explain that the fetus has a 50% chance of having the disorder.
c. Discuss options with the couple, including amniocentesis to determine whether the fetus is affected.
d. Refer the couple to a psychologist for emotional support. - Answer ANS: C - Genetic testing, including
amniocentesis, would need to be performed to determine whether the fetus is affected. The couple
should be given information about the likelihood of having another baby with this disorder so that they
can make an informed decision. A genetic counselor is the best source for determining genetic
probability ratios. The couple eventually may need emotional support, but the status of the pregnancy
must be determined first.
The nurse is assessing the knowledge of new parents with a child born with maple syrup urine disease
(MSUD). This is an autosomal recessive inherited disorder, which means that:
, a. Both genes of a pair must be abnormal for the disorder to be expressed.
b. Only one copy of the abnormal gene is required for the disorder to be expressed.
c. The disorder occurs in males and heterozygous females.
d. The disorder is carried on the X chromosome. - Answer ANS: A - MSUD is a type of autosomal
recessive inheritance disorder in which both genes of a pair must be abnormal for the disorder to be
expressed. MSUD is not an X-linked dominant or recessive disorder or an autosomal dominant
inheritance disorder.
In presenting to obstetric nurses interested in genetics, the genetic nurse identifies the primary risk(s)
associated with genetic testing as:
a. Anxiety and altered family relationships.
b. Denial of insurance benefits.
c. High false-positive results associated with genetic testing.
d. Ethnic and socioeconomic disparity associated with genetic testing. - Answer ANS: B - Decisions about
genetic testing are shaped by socioeconomic status and the ability to pay for the testing. Some types of
genetic testing are expensive and are not covered by insurance benefits. Anxiety and altered family
relationships, high false-positive results, and ethnic and socioeconomic disparity are factors that may be
difficulties associated with genetic testing, but they are not risks associated with testing.
A mans wife is pregnant for the third time. One child was born with cystic fibrosis, and the other child is
healthy. The man wonders what the chance is that this child will have cystic fibrosis. This type of testing
is known as:
a. Occurrence risk.
c. Predictive testing.
b. Recurrence risk.
d. Predisposition testing. - Answer ANS: B - The couple already has a child with a genetic disease so they
will be given a recurrence risk test. If a couple has not yet had children but are known to be at risk for
having children with a genetic disease, they are given an occurrence risk test. Predictive testing is used
to clarify the genetic status of an asymptomatic family member. Predisposition testing differs from
presymptomatic testing in that a positive result does not indicate 100% risk of a condition developing.
A key finding from the Human Genome Project is:
