You are a genetic counselor working with a phenotypically normal young couple who have been referred because the wife has a family history of a mitochondrial disorder that results in considerable dysfunction. What is the most important consideration you can suggest?
A)to refrain from having children that are hers biologically
B)that she be tested to find out what percentage of her mitochondria bear the mutation
C)that both husband and wife have mtDNA testing for the sequence in question
D)that her affected mother's DNA be tested
E)that they consider having only sons

Question

Quizplus · Accepted Answer

Testing the wife to find out what percentage of her mitochondria bear the mutation is important because mitochondrial disorders can be transmitted maternally, meaning that the offspring inherit their mitochondria from their mother. If the wife has a high percentage of mutated mitochondria, the risk of her passing on the disorder to her offspring increases. This information can inform the couple's decision about reproduction options, such as using donor eggs or pursuing adoption. Testing the husband and wife for the sequence in question (choice C) is also important, but knowing the wife's mitochondrial mutation load is a more pressing consideration. Refraining from having children biologically (choice A) or only having sons (choice E) may not be viable options for some couples, and testing the affected mother's DNA (choice D) may not provide useful information since it is already known that she carries the mutation.

You Are a Genetic Counselor Working with a Phenotypically Normal