Genetic Counselor ABGC EXAM PRACTICE-QUESTION AND COLLECT
ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2025/2026 Q&A
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1. Which inheritance pattern is most consistent with a condition that affects both males and
females equally across multiple generations?
A. Autosomal recessive
B. Autosomal dominant
C. X-linked recessive
D. Mitochondrial
Rationale: Autosomal dominant traits typically affect both sexes equally and appear in every
generation.
2. Which of the following best explains anticipation in trinucleotide repeat disorders?
A. Phenotype becomes less severe in later generations
B. Disorder skips generations
C. Earlier age of onset and more severe symptoms in subsequent generations
D. Disease is only passed through males
Rationale: Anticipation refers to increasing severity or earlier onset of symptoms in succeeding
generations, seen in disorders like Huntington’s disease and myotonic dystrophy.
3. A couple who are both carriers for cystic fibrosis ask about recurrence risk. What is the
chance their child will have CF?
A. 100%
B. 75%
C. 25%
D. 50%
Rationale: CF is autosomal recessive; two carrier parents have a 25% chance of having an
affected child.
4. Which molecular technique is best for detecting large chromosomal deletions or
duplications?
A. Sanger sequencing
B. PCR
C. Microarray (array-CGH)
D. Restriction fragment length polymorphism
,Rationale: Microarray is used to detect copy number variations such as large
deletions/duplications.
5. Which counseling technique emphasizes reflecting a client’s emotions and validating
their experience?
A. Information giving
B. Empathic listening
C. Problem-solving
D. Risk assessment
Rationale: Empathic listening validates feelings and helps establish rapport in genetic
counseling.
6. Which of the following is an example of nondirectiveness in genetic counseling?
A. Telling a patient what decision is best for them
B. Providing balanced information so clients can make informed choices
C. Recommending termination of pregnancy
D. Withholding risk information
Rationale: Nondirectiveness means supporting autonomy by providing unbiased, accurate
information.
7. Which of the following is most characteristic of X-linked recessive inheritance?
A. Affected males are more common than affected females
B. Both sexes equally affected
C. Trait appears in every generation
D. Males cannot transmit the mutation
Rationale: In X-linked recessive inheritance, males are more often affected due to having only
one X chromosome.
8. Which disorder is caused by imprinting errors?
A. Huntington’s disease
B. Cystic fibrosis
C. Prader-Willi and Angelman syndromes
D. Sickle cell anemia
, Rationale: Imprinting disorders result from parent-of-origin effects on gene expression, as seen
in Prader-Willi and Angelman syndromes.
9. What is the most likely recurrence risk for Down syndrome due to nondisjunction in a
35-year-old woman?
A. 100%
B. 50%
C. 1% above age-related risk
D. 25%
Rationale: Nondisjunction usually occurs sporadically; recurrence risk is ~1% plus maternal
age-related risk.
10. In a pedigree, what does a double horizontal line between partners represent?
A. Divorce
B. Consanguinity
C. Adoption
D. Dizygotic twins
Rationale: A double line denotes consanguinity (partners are related).
11. What type of genetic testing is most appropriate for a child with developmental delay
and multiple congenital anomalies?
A. Targeted mutation analysis
B. Chromosomal microarray
C. Karyotype
D. Prenatal testing
Rationale: Microarray is the first-line test for unexplained developmental delay or congenital
anomalies.
12. Which is an ethical principle most closely aligned with nondirectiveness?
A. Beneficence
B. Non-maleficence
C. Autonomy
D. Justice
Rationale: Nondirectiveness supports autonomy, the client’s right to make their own decisions.
ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2025/2026 Q&A
|INSTANT DOWNLOAD PDF
1. Which inheritance pattern is most consistent with a condition that affects both males and
females equally across multiple generations?
A. Autosomal recessive
B. Autosomal dominant
C. X-linked recessive
D. Mitochondrial
Rationale: Autosomal dominant traits typically affect both sexes equally and appear in every
generation.
2. Which of the following best explains anticipation in trinucleotide repeat disorders?
A. Phenotype becomes less severe in later generations
B. Disorder skips generations
C. Earlier age of onset and more severe symptoms in subsequent generations
D. Disease is only passed through males
Rationale: Anticipation refers to increasing severity or earlier onset of symptoms in succeeding
generations, seen in disorders like Huntington’s disease and myotonic dystrophy.
3. A couple who are both carriers for cystic fibrosis ask about recurrence risk. What is the
chance their child will have CF?
A. 100%
B. 75%
C. 25%
D. 50%
Rationale: CF is autosomal recessive; two carrier parents have a 25% chance of having an
affected child.
4. Which molecular technique is best for detecting large chromosomal deletions or
duplications?
A. Sanger sequencing
B. PCR
C. Microarray (array-CGH)
D. Restriction fragment length polymorphism
,Rationale: Microarray is used to detect copy number variations such as large
deletions/duplications.
5. Which counseling technique emphasizes reflecting a client’s emotions and validating
their experience?
A. Information giving
B. Empathic listening
C. Problem-solving
D. Risk assessment
Rationale: Empathic listening validates feelings and helps establish rapport in genetic
counseling.
6. Which of the following is an example of nondirectiveness in genetic counseling?
A. Telling a patient what decision is best for them
B. Providing balanced information so clients can make informed choices
C. Recommending termination of pregnancy
D. Withholding risk information
Rationale: Nondirectiveness means supporting autonomy by providing unbiased, accurate
information.
7. Which of the following is most characteristic of X-linked recessive inheritance?
A. Affected males are more common than affected females
B. Both sexes equally affected
C. Trait appears in every generation
D. Males cannot transmit the mutation
Rationale: In X-linked recessive inheritance, males are more often affected due to having only
one X chromosome.
8. Which disorder is caused by imprinting errors?
A. Huntington’s disease
B. Cystic fibrosis
C. Prader-Willi and Angelman syndromes
D. Sickle cell anemia
, Rationale: Imprinting disorders result from parent-of-origin effects on gene expression, as seen
in Prader-Willi and Angelman syndromes.
9. What is the most likely recurrence risk for Down syndrome due to nondisjunction in a
35-year-old woman?
A. 100%
B. 50%
C. 1% above age-related risk
D. 25%
Rationale: Nondisjunction usually occurs sporadically; recurrence risk is ~1% plus maternal
age-related risk.
10. In a pedigree, what does a double horizontal line between partners represent?
A. Divorce
B. Consanguinity
C. Adoption
D. Dizygotic twins
Rationale: A double line denotes consanguinity (partners are related).
11. What type of genetic testing is most appropriate for a child with developmental delay
and multiple congenital anomalies?
A. Targeted mutation analysis
B. Chromosomal microarray
C. Karyotype
D. Prenatal testing
Rationale: Microarray is the first-line test for unexplained developmental delay or congenital
anomalies.
12. Which is an ethical principle most closely aligned with nondirectiveness?
A. Beneficence
B. Non-maleficence
C. Autonomy
D. Justice
Rationale: Nondirectiveness supports autonomy, the client’s right to make their own decisions.
