Red-green color blindness shows X-linked recessive inheritance.Assume "X" is normal,"X1" is recessive for the trait,and "Y" is normal.Then,an individual with the genotype "XX1" will be a:
A) normal female and a carrier.
B) color-blind male.
C) normal female and not a carrier.
D) normal male.

Question

Quizplus · Accepted Answer

Females have two copies of the X chromosome, so even if one is carrying the recessive allele for color blindness, the other X chromosome can compensate and provide the normal allele. Therefore, females with the genotype "XX1" are normal and carriers of the color blindness trait.

Red-Green Color Blindness Shows X-Linked Recessive Inheritance