The presence of freckles is a dominant feature. A woman with freckles marries a man

The presence of freckles is a dominant feature. A woman with freckles marries a man with freckles, what is the probability of having children without freckles.

Let’s designate the gene that causes the development of freckles in humans as K, then the gene that causes their absence will be designated as k.

People with genotype kk homozygous for the recessive gene will not have freckles. Such a genotype can have a person who inherited recessive genes from both parents.

Parents with freckles in order to be able to produce a child without freckles must both be heterozygous carriers of the recessive gene.

Let us designate the genotypes of both parents as Kk. People with this genotype are capable of producing two types of germ cells – K and k. Their possible offspring are represented by the following options:

homozygous freckled children (KK) – 25%;

homozygous children without freckles (kk) – 25%;

heterozygous freckled children (Kk) – 50%.

Answer: if both parents are heterozygous, the probability of having a child without freckles is 25%.