In humans, brown eye color (A) and the ability to use the right hand (B) are inherited as dominant traits.

In humans, brown eye color (A) and the ability to use the right hand (B) are inherited as dominant traits. Blue eyes (a) and the ability to use the left hand (c) are inherited as recessive traits. A blue-eyed young man with a right hand, homozygous for both traits, marries a brown-eyed right-handed man who is heterozygous for both traits. What offspring can be expected from this marriage?

The blue-eyed right-hander is conditionally homozygous for both gene pairs. Let’s write it as aaBB, and the spermatozoa produced by his body – as aB.

The girl is a diheterozygous brown-eyed right-hander – AaBb. It will produce four types of oocytes – ab, AB, aB and Ab.

The offspring expected from a given married couple will be represented by the following options:

children – right-handed people with blue eyes (aaBb, aaBB) – 50%;

children – right-handed with brown eyes (AaBB, AaBb) – 50%.