Question

Aniridia is a type of blindness due to a single dominant gene. Migraine headache is the result of a different dominant gene. A man with aniridia, but normal headaches whose mother was not blind, marries a woman who suffers from migraines and has normal vision but whose father did not have migraine headaches. What is the expected proportion of their children that would have both aniridia and migraines together

Answer 1

Answer:

$\frac{1}{4}$  = 25%

Explanation:

Aniridia is a type of blindness due to a single dominant gene---- Let Aniridia allele be A

Migraine headache is the result of a different dominant gene----- Let Migraine allele be M

Let normal headache allele be h

Let normal vision allele be v

If A man with aniridia, but normal headaches i.e Ah marries a woman who suffers from migraines and has normal vision i.e Mv

What is the expected proportion of their children that would have both aniridia and migraines together?

The punnet square for this cross is shown below as:

           A           h

M        AM         hM

v         Av          hv

The offspring traits are as follows (AM, hM, Av, hv)

AM----- Aniridia and Migraine

hM------ normal headache and Migraine

Av------- Aniridia and normal vision

hv------- normal headache and normal vision

The expected proportion of their children that would have both aniridia and migraine together is $\frac{1}{4}$   = 25%