Julie has Harman's ataxia hh) and also has achrondoplasia Aa). Josh is a carrier for Harman's ataxia, an autosomal recessive disorder, and has achondroplasia Aa), which is an autosomal dominant trait. AA human embryos do not survive beyond the first few cell divisions. What is the probability that a child born to them would have only Harman's ataxia? Assume the genes are unlinked.

Question

Quizplus · Accepted Answer

The probability of a child having only Harman's ataxia (hh) and not achondroplasia (aa) is calculated by multiplying the probabilities of inheriting each condition. The probability of inheriting hh is 1/2 (from Hh x hh), and the probability of inheriting aa is 1/3 (from Aa x Aa, excluding AA which is lethal). Therefore, the combined probability is 1/2 * 1/3 = 1/6.

Julie Has Harman's Ataxia Hh) and Also Has Achrondoplasia Aa)