Question

Night blindness (n) is a sex-linked recessive trait. A woman who is night blind marries a man who is not night blind. What are the genotypes of both individuals?​

Answer 1

Answer:

Genotype of night blind woman -  XnXn

Genotype of normal man - XY

Explanation:

Given

Night blindness (n) is a sex-linked recessive trait. Let us say it is X linked recessive

In this case a man with XY genotype having a diseased X allele will be night blind while a woman will have night blindness if both the X allele are diseased  . In case if only one X allele is diseased in women then, she will be a carrier of night blindness defect

Genotype of night blind woman -  XnXn

Genotype of normal man - XY