In autosomal recessive inheritance, two unaffected carrier parents have a child affected by a genetic disorder. What is the probability the next child will be affected?

Prepare for the NBME Form 11 Test with targeted flashcards and multiple-choice questions. Each question includes hints and explanations to aid learning. Boost your readiness for exam day!

Multiple Choice

In autosomal recessive inheritance, two unaffected carrier parents have a child affected by a genetic disorder. What is the probability the next child will be affected?

In autosomal recessive inheritance, two unaffected carriers each have one normal and one mutated allele (Aa). Across a pregnancy, the child can be AA (unaffected noncarrier) 25% of the time, Aa (carrier) 50%, or aa (affected) 25%. Therefore, the chance a new child is affected is 25% (1 in 4). The outcome of prior pregnancies does not change the odds for the next one—the probabilities are the same for each pregnancy.

In autosomal recessive inheritance, two unaffected carrier parents have a child affected by a genetic disorder. What is the probability the next child will be affected?

Prepare for the NBME Form 11 Test with targeted flashcards and multiple-choice questions. Each question includes hints and explanations to aid learning. Boost your readiness for exam day!

In autosomal recessive inheritance, two unaffected carrier parents have a child affected by a genetic disorder. What is the probability the next child will be affected?

Get the latest from Passetra