Question

Baldness (B) is inherited as X-linked dominant disease. An affected male marries a homozygous recessive female. What is the probability that their male offspring will be affected by this disease. (Hint: determine the genotype of the parents and then perform the Punnett square)
0%


25%


50%


100%

Answer 1

This can be solved with Punnett squares. The affected male has the $X^{B} y$ genotype, and the female is homozygous recessive. This means that she does not carry this, and therefore, will have the genotype XᵇXᵇ

While doing this Punnett Square, keep in mind that in order to have the male offspring affected, their genotype has to be $X^{B} y$

Since there are no $X^{B} y$, the probability of their male offspring inheriting this disease is 0%