A blue-eyed woman is a carrier of color blindness, married a heterozygous brown-eyed healthy man.

A blue-eyed woman is a carrier of color blindness, married a heterozygous brown-eyed healthy man. How will children be born from this marriage?

Let’s designate the gene that causes the development of brown eyes in humans as K, then the gene that causes the development of blue eyes will be k.

It is known that the gene that causes the development of color blindness is inherited in the X chromosome. Let’s designate it as X d, then the chromosome with the gene for normal color vision will be X D.

A heterozygous brown-eyed male with normal color vision has the genotype

KkX DY. It produces four types of sperm – KX D, kY, KY, kX D.

The blue-eyed mother carrying the pathological gene for color blindness has the genotype

kkX DX d. This woman produces two types of eggs – kX D, kX d.

The offspring of this married couple will be represented by the following possible options:

girls with normal color vision and brown eyes (KkX D X D, KkX D X d) – 25%;

boys with normal color vision and blue eyes (kkX D Y) – 12.5%;

boys with normal color vision and brown eyes (KkX D Y) – 12.5%;

girls with normal color vision and blue eyes (kkX D X D, kkX D X d) – 25%;

boys with color blindness and blue eyes (kk X dY) – 12.5%;

boys with color blindness and brown eyes (Kk X dY) – 12.5%.