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Discussion Starter · #1 ·
A woman gives birth to a child apparent achondroplasia. Two other siblings are of normal stature for their age. A genetic consultation group is asked to review the case. Both parents are 42 years old, and there is no previous family history of this condition.

What is the most likely explanation for the occurrence of this defect in this family?

a. gonadal mosaicism
b. incomplete penetrance
c. new mutation in the maternal gamete
d. new mitation in the paternal gamete
e. nonpaternity
 

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Yeah. It is D. In achondroplasia, gene mutation increase with paternal age (fibroblast growth factor receptor gene)
 

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Discussion Starter · #7 ·
yep guys d) dad is the problem here. this is a new mutation. risk increases with paternal age > 35 yo
 
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