The deaf-mute gene is recessive to the normal hearing gene. What offspring can be expected from the marriage

The deaf-mute gene is recessive to the normal hearing gene. What offspring can be expected from the marriage of a deaf-mute father with a normally hearing woman.

The deaf-mute gene is recessive to the normal hearing gene. What offspring can be expected from the marriage of a deaf-mute father with a normally hearing woman.

Let’s designate the gene responsible for deaf-dumbness as “c”, then the corresponding dominant gene will be “C”.

The father is deaf-mute, therefore, his genotype will look like “cc”, since a necessary condition for the phenotypic realization of a recessive trait is his homozygosity. Such a father produces type “c” spermatozoa.

A woman hears normally, her genotype can be either Cc or CC.

Let’s consider both options.

Woman SS. It produces C and C eggs. Possible offspring of the couple: normally hearing (Cc) and deaf-mute children (Cc) in a ratio of 50% to 50%.
SS woman. Produces C. oocytes. Possible offspring of the couple: 100% normal hearing children (Cc).