Question

If the mother is a carrier of colour blindness and the father is normal, show the possible genotype and phenotype of the offspring of the next generation, with the help of a punnet square.

Answer 1

Colour blindness is an X-linked recessive disorder. In the above question, Mother is a carrier for colourblindness. Therefore, her genotype must be X^C X. The father is normal, hence his genotype must be XY. By using punnet square, the possible genotypes and phenotypes in next generation will be:

	X	Y
X^C	X^C X	X^C Y
X	XX	XY

The possible genotypes are- X^C X, X^C Y, XX and XY. The four possible phenotypes are- Carrier Daughter (X^C X), Affected son (X^C Y), Normal daughter (XX), Normal son (XY).