ABGC BOARDS PRACTICE EXAM QUESTIONS WITH 100%
VERIFIED ANSWERS |2026/2027 UPDATE | A+ GRADED
A 35-year-old male patient presents to a genetic counselor with a complex medical history. He
has a personal history of macrocephaly, multiple hamartomatous polyps in his gastrointestinal
tract, and lipomas. His family history is remarkable for several close relatives with breast cancer.
The patient is concerned about his own cancer risk. After a thorough evaluation, the genetic
counselor suspects the possibility of a hereditary cancer syndrome. Which of the following
genes should the genetic counselor consider testing for in this patient, given the clinical
presentation?
A) MEN1
B) RET
C) TSC1
D) PTEN - Answer -D) PTEN
You evaluate an individual for a hereditary cancer predisposition and they tell you they have a
personal history of a sebaceous carcinoma. What other cancer type do you want to ask about?
A) Uterine cancer
B) Prostate Cancer
C) Melanoma
D) Colorectal - Answer -D) Colorectal
A 40 year old woman presents to clinic with a family history of follicular thyroid cancer in her
brother. She noted that her mother had endometrial cancer and a maternal aunt had breast
1|Page
,cancer but she could not recall the age of diagnoses. You notice she has several lumps on her
nose which you noted from her chart are benign. She said her mother also had these lumps. She
is worried that she will also get thyroid cancer because she has some thyroid lesions. Which
condition is moving to the top of your differential?
A) Peutz-Jeger Syndrome
B) Li-Fraumeni
C) PTEN Hamartoma
D) Multiple Endocrine Neoplasia Type 2A - Answer -C) PTEN Hamartoma
Defects in the genes that encode proteins involved in homologous recombination repair cause:
A) Aicardi-Gutieres syndrome
B) Hereditary Breast and Ovarian Cancer
C) Lynch Syndrome
D) Retinoblastoma - Answer -B) Hereditary Breast and Ovarian Cancer
A 22 yo has Prader-Willi features. Work up included a microarray that found a deletion, which
included the APC gene. What is the next BEST step?
A) Offer APC testing for the patient's parents
B) Counsel the patient that this finding is normal among people with PWS
C) Inform the patient that they need a colonoscopy
D) Explain that this is beyond the scope of practice for a genetic counselor - Answer -C) Inform
the patient that they need a colonoscopy
2|Page
,In a family with a history of a rare autosomal dominant disorder, a child is born unaffected by
the condition, even though one of the parents is affected. What is the most likely explanation
for this situation?
A) The child carries two copies of the dominant allele.
B) The disorder exhibits incomplete penetrance.
C) The disorder is X-linked recessive.
D) The child underwent somatic mutation after conception. - Answer -B) The disorder exhibits
incomplete penetrance.
A woman with a known mitochondrial DNA (mtDNA) mutation that causes a mitochondrial
disorder is planning to have children. What can you tell her about the inhertiance of this
condition?
A) Her children will definitely inherit the mitochondrial disorder
B) Her children will not inherit the mitochondrial disorder
C) The mitochondrial disorder will only affect her daughters, not her sons
D) The risk of her children inheriting the mitochondrial disorder depends on the specific
mutation and the percentage of mutated mtDNA in the mitochondria in her eggs - Answer -D)
The risk of her children inheriting the mitochondrial disorder depends on the specific mutation
and the percentage of mutated mtDNA in the mitochondria in her eggs
A couple has a daughter with clefting due to Van der Woude syndrome, an autosomal dominant
disorder that presents in childhood. After a careful exam, neither parent has been found to
show symptoms. What is the most likely explanation for this family?
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, A) Mitochondrial inheritance
B) Reduced penetrance
C) Sex influenced inheritance
D) Variable expressivity - Answer -B) Reduced penetrance
In a family with a history of a single gene disorder, a child inherits the mutated allele from their
mother and remains unaffected, while their cousin inherits the same mutated allele from their
father and exhibits symptoms of the disorder. What best explains this difference in phenotypic
expression?
A) The child with the mother's allele underwent spontaneous mutation correction.
B) The cousin with the father's allele has a de novo mutation.
C) The disorder is subject to genomic imprinting.
D) The disorder is caused by mitochondrial DNA mutations. - Answer -C) The disorder is subject
to genomic imprinting.
Ultrasonography of a 26-year-old woman at 16 weeks gestation shows fetal findings consistent
with osteogenesis imperfecta, type II. The woman had a previous fetus affected with the same
condition. The woman and her husband are healthy and have no obvious clinical characteristics
of osteogenesis imperfecta. Which of the following is the MOST likely explanation for this
recurrence?
A) Autosomal recessive inheritance
B) De novo mutation
C) Germline mosaicism
4|Page
VERIFIED ANSWERS |2026/2027 UPDATE | A+ GRADED
A 35-year-old male patient presents to a genetic counselor with a complex medical history. He
has a personal history of macrocephaly, multiple hamartomatous polyps in his gastrointestinal
tract, and lipomas. His family history is remarkable for several close relatives with breast cancer.
The patient is concerned about his own cancer risk. After a thorough evaluation, the genetic
counselor suspects the possibility of a hereditary cancer syndrome. Which of the following
genes should the genetic counselor consider testing for in this patient, given the clinical
presentation?
A) MEN1
B) RET
C) TSC1
D) PTEN - Answer -D) PTEN
You evaluate an individual for a hereditary cancer predisposition and they tell you they have a
personal history of a sebaceous carcinoma. What other cancer type do you want to ask about?
A) Uterine cancer
B) Prostate Cancer
C) Melanoma
D) Colorectal - Answer -D) Colorectal
A 40 year old woman presents to clinic with a family history of follicular thyroid cancer in her
brother. She noted that her mother had endometrial cancer and a maternal aunt had breast
1|Page
,cancer but she could not recall the age of diagnoses. You notice she has several lumps on her
nose which you noted from her chart are benign. She said her mother also had these lumps. She
is worried that she will also get thyroid cancer because she has some thyroid lesions. Which
condition is moving to the top of your differential?
A) Peutz-Jeger Syndrome
B) Li-Fraumeni
C) PTEN Hamartoma
D) Multiple Endocrine Neoplasia Type 2A - Answer -C) PTEN Hamartoma
Defects in the genes that encode proteins involved in homologous recombination repair cause:
A) Aicardi-Gutieres syndrome
B) Hereditary Breast and Ovarian Cancer
C) Lynch Syndrome
D) Retinoblastoma - Answer -B) Hereditary Breast and Ovarian Cancer
A 22 yo has Prader-Willi features. Work up included a microarray that found a deletion, which
included the APC gene. What is the next BEST step?
A) Offer APC testing for the patient's parents
B) Counsel the patient that this finding is normal among people with PWS
C) Inform the patient that they need a colonoscopy
D) Explain that this is beyond the scope of practice for a genetic counselor - Answer -C) Inform
the patient that they need a colonoscopy
2|Page
,In a family with a history of a rare autosomal dominant disorder, a child is born unaffected by
the condition, even though one of the parents is affected. What is the most likely explanation
for this situation?
A) The child carries two copies of the dominant allele.
B) The disorder exhibits incomplete penetrance.
C) The disorder is X-linked recessive.
D) The child underwent somatic mutation after conception. - Answer -B) The disorder exhibits
incomplete penetrance.
A woman with a known mitochondrial DNA (mtDNA) mutation that causes a mitochondrial
disorder is planning to have children. What can you tell her about the inhertiance of this
condition?
A) Her children will definitely inherit the mitochondrial disorder
B) Her children will not inherit the mitochondrial disorder
C) The mitochondrial disorder will only affect her daughters, not her sons
D) The risk of her children inheriting the mitochondrial disorder depends on the specific
mutation and the percentage of mutated mtDNA in the mitochondria in her eggs - Answer -D)
The risk of her children inheriting the mitochondrial disorder depends on the specific mutation
and the percentage of mutated mtDNA in the mitochondria in her eggs
A couple has a daughter with clefting due to Van der Woude syndrome, an autosomal dominant
disorder that presents in childhood. After a careful exam, neither parent has been found to
show symptoms. What is the most likely explanation for this family?
3|Page
, A) Mitochondrial inheritance
B) Reduced penetrance
C) Sex influenced inheritance
D) Variable expressivity - Answer -B) Reduced penetrance
In a family with a history of a single gene disorder, a child inherits the mutated allele from their
mother and remains unaffected, while their cousin inherits the same mutated allele from their
father and exhibits symptoms of the disorder. What best explains this difference in phenotypic
expression?
A) The child with the mother's allele underwent spontaneous mutation correction.
B) The cousin with the father's allele has a de novo mutation.
C) The disorder is subject to genomic imprinting.
D) The disorder is caused by mitochondrial DNA mutations. - Answer -C) The disorder is subject
to genomic imprinting.
Ultrasonography of a 26-year-old woman at 16 weeks gestation shows fetal findings consistent
with osteogenesis imperfecta, type II. The woman had a previous fetus affected with the same
condition. The woman and her husband are healthy and have no obvious clinical characteristics
of osteogenesis imperfecta. Which of the following is the MOST likely explanation for this
recurrence?
A) Autosomal recessive inheritance
B) De novo mutation
C) Germline mosaicism
4|Page
