A blue-eyed man whose parents had brown eyes married a woman with brown eyes, whose father had blue

A blue-eyed man whose parents had brown eyes married a woman with brown eyes, whose father had blue eyes and whose mother had brown. From this marriage, a child with brown eyes was born. What genotypes do all of the individuals named here have?

Brown-eyed is usually the dominant feature. Let’s designate the gene that determines brown eyes as A, then the blue-eyed gene will be a.

The woman has brown eyes, but her father has blue eyes, he is aa, his sperm carry only the gene, and therefore, in order to have brown eyes, a woman must be at least heterozygous to Aa.

The man, the father of the child, is also blue-eyed, like the father of the woman – aa.

A brown-eyed child from a blue-eyed father will be heterozygous – Aa.

It is reliably impossible to determine the genotype of a woman’s brown-eyed mother based on the information provided in the problem statement, however, we will write down the possible options – AA or Aa.