Genetic Counseling Boards Review Exam
Questions & Answers
LMNA G608G - A young patient (5yrs) presents for the first time to
a new dentist with crowded teeth, making them very hard to clean.
In further exploration of the issue, she learns that the child had
delayed eruption of his teeth. The patient's mother also relays that
her pediatrician has several times noted how prominent the veins
of his scalp are and his short stature.
However, she thinks that this is just part of the spectrum seen in
their family given that she herself is quite short and has fair skin,
making it easier to see her veins. You speak with the dentist who
isn't sure whether or not to refer the family. You are most
concerned about what mutation:
LMNA
G1138A
LMNA G608G
FGFR3 Exon 11
deletion FGFR3
G608G
ii, iii - The current prenatal screening test used in your clinic has a
sensitivity of 96% and a specificity of 89%. In speaking to
representatives from the lab, you learn that they want to adjust
their reading of this test by increasing the cutoff levels. Which of
the following effects would you expect to see if this change was
implemented?
i. Increase
sensitivity ii.
Increase
specificity
iii. Decrease false
positives iv. Decrease
false negatives
None of the above are reasons that MTHFR testing should be
conducted - Which of the following scenarios would MTHFR testing
,be appropriate?
a. Recurrent pregnancy loss
b. Thrombophilia, in the presence of negative primary
thrombophilia testing c. Open neural tube defect identified on
prenatal ultrasound, despite adequate folic acid intake
d. Patients about to start a methotrexate chemotherapy
regimen e. none of the above
,c - Genetic drift is an exception of which of the following
assumptions of Hardy Weinberg:
a. No
mutation b.
No migration
c. Population is infinitely
large d. Random mating
Marfan Syndrome (utility of testing influenced by physical
evaluation) - For which indication would telehealth service delivery
model be inappropriate? Breast cancer
Marfan
Syndrome
Carrier
screening
Cascade
testing
1/100
--With incidence of disease in AJ being 1/1000, man's carrier risk is
about 1/18
--Woman's risk of being a carrier is 2/3 since her parents are
obligate carriers and she is not affected
-- ⅔ x ½ x 1/18 x ½ = 1/108 = ~1/100 - A couple is seen for
preconception counseling. The woman's brother has Gaucher
disease, and she has Ashkenazi Jewish ancestry (Gaucher disease
incidence of 1 in 1,000).
Before doing any genetic testing, which of the following is closest
to the risk of the couple having an affected child?
1/50
1/100
1/150
1/200
c. Missense mutation in EDA1 *The condition being described is
hypohidrotic ectodermal dysplasia which is most often caused by
EDA1 mutations. - You are meeting a 3 year old little boy in the
, pediatric genetics clinic. His parents were referred to the clinic by
his astute dentist who mentioned he did not have as many teeth as
expected. On meeting the boy, you also note he has sparse hair.
His parents also tell you he tends to get overheated when he
Questions & Answers
LMNA G608G - A young patient (5yrs) presents for the first time to
a new dentist with crowded teeth, making them very hard to clean.
In further exploration of the issue, she learns that the child had
delayed eruption of his teeth. The patient's mother also relays that
her pediatrician has several times noted how prominent the veins
of his scalp are and his short stature.
However, she thinks that this is just part of the spectrum seen in
their family given that she herself is quite short and has fair skin,
making it easier to see her veins. You speak with the dentist who
isn't sure whether or not to refer the family. You are most
concerned about what mutation:
LMNA
G1138A
LMNA G608G
FGFR3 Exon 11
deletion FGFR3
G608G
ii, iii - The current prenatal screening test used in your clinic has a
sensitivity of 96% and a specificity of 89%. In speaking to
representatives from the lab, you learn that they want to adjust
their reading of this test by increasing the cutoff levels. Which of
the following effects would you expect to see if this change was
implemented?
i. Increase
sensitivity ii.
Increase
specificity
iii. Decrease false
positives iv. Decrease
false negatives
None of the above are reasons that MTHFR testing should be
conducted - Which of the following scenarios would MTHFR testing
,be appropriate?
a. Recurrent pregnancy loss
b. Thrombophilia, in the presence of negative primary
thrombophilia testing c. Open neural tube defect identified on
prenatal ultrasound, despite adequate folic acid intake
d. Patients about to start a methotrexate chemotherapy
regimen e. none of the above
,c - Genetic drift is an exception of which of the following
assumptions of Hardy Weinberg:
a. No
mutation b.
No migration
c. Population is infinitely
large d. Random mating
Marfan Syndrome (utility of testing influenced by physical
evaluation) - For which indication would telehealth service delivery
model be inappropriate? Breast cancer
Marfan
Syndrome
Carrier
screening
Cascade
testing
1/100
--With incidence of disease in AJ being 1/1000, man's carrier risk is
about 1/18
--Woman's risk of being a carrier is 2/3 since her parents are
obligate carriers and she is not affected
-- ⅔ x ½ x 1/18 x ½ = 1/108 = ~1/100 - A couple is seen for
preconception counseling. The woman's brother has Gaucher
disease, and she has Ashkenazi Jewish ancestry (Gaucher disease
incidence of 1 in 1,000).
Before doing any genetic testing, which of the following is closest
to the risk of the couple having an affected child?
1/50
1/100
1/150
1/200
c. Missense mutation in EDA1 *The condition being described is
hypohidrotic ectodermal dysplasia which is most often caused by
EDA1 mutations. - You are meeting a 3 year old little boy in the
, pediatric genetics clinic. His parents were referred to the clinic by
his astute dentist who mentioned he did not have as many teeth as
expected. On meeting the boy, you also note he has sparse hair.
His parents also tell you he tends to get overheated when he
