In humans, hair color is controlled by two interacting genes. The same pigment, melanin, is present in both brown-haired and blond-haired people, but brown hair has much more of it. Brown hair (B) is dominant over blonde hair (b). Whether any melanin can be synthesized depends on another gene. The dominant form (M) allows melanin synthesis; the recessive form (m) prevents melanin synthesis. Homozygous recessive (mm) individuals are albino. What will be the expected genotypic and phenotypic proportions in the children of the following parents: double heterozygous brown-haired mother and blonde-haired heterozygous melanin production (Mm) father?
