In a case in which two individuals who are heterozygous carriers of an autosomal recessive condition have a child, what is the probability that the child is a carrier of a single copy of the mutation?
A)50%
B)25%
C)100%
D)0%
E)75%

Question

Quizplus · Accepted Answer

When both parents are heterozygous carriers of an autosomal recessive condition, their genotypes can be represented as Aa (where A is the normal allele and a is the mutated allele). The possible genotypes for their offspring, based on simple Mendelian genetics, are AA, Aa, Aa, and aa. Thus, there is a 50% chance (2 out of 4 possibilities) that the child will inherit one copy of the mutated allele and one copy of the normal allele, making them a carrier (Aa).

In a Case in Which Two Individuals Who Are Heterozygous