Genetic testing of an asymptomatic woman whose sister is positive for the mutation that is responsible for an autosomal-dominant disorder that has a 70% penetrance ratewould fall into which testing category?
A)Diagnostic predisposition
B)Diagnostic presymptomatic
C)Predictive predisposition
D)Predictive presymptomatic

Question

Quizplus · Accepted Answer

The test is predictive rather than diagnostic because the woman does not have any symptoms of the disorder. So, the test is not being performed to confirm or rule out a disorder diagnosis. The test is also considered "predisposition" testing rather than "presymptomatic" testing because the disorder has a 70% penetrance rate. This means that even if the woman is positive, she has a 30% chance of never developing symptoms but has a genetic predisposition to the disorder.

Genetic Testing of an Asymptomatic Woman Whose Sister Is Positive