question_answer

A women with albinic father marries an albinic man. The proportion of her progeny is

A)  2 normal: 1 albinic

B)  All normal

C)  All albinic

D)  1 normal: 1 albinic

Correct Answer: D

Solution :

                Albinism is an autosomal recessive metabolic disorder. It is characterised by the complete or partial absence of pigment in the skin, hair and eyes due to the absence or defect of tyrosinase, a copper-containing enzyme involved in the production of melanin. An albino (rr) man if marries a normal women will have a progeny carrying one recessive allele and one normal allele in a heterozygous (Rr). Thus, his daughter will be with Rr genes. And when the heterozygous woman marries a albinic man the proportion of her progeny is: Therefore, the ratio is 1 normal: 1 albinic