Biology - Principles of Inheritance and Variation Question with Solution | TestHub

Sickle-cell anaemia is an autosomal recessive disorder.

Let the normal allele be $H{b}^A$ and the sickle-cell allele be $H{b}^S$.

The genotype of the carrier man is $H{b}^{A}H{b}^S$ and the carrier woman is $H{b}^{A}H{b}^S$.

The cross between them is $H{b}^{A}H{b}^S\times H{b}^{A}H{b}^S$.

The possible genotypes of the offspring are:
$25\%$ $H{b}^{A}H{b}^A$ (Normal)
$50\%$ $H{b}^{A}H{b}^S$ (Carrier)
$25\%$ $H{b}^{S}H{b}^S$ (Affected)

The chances of having carrier children is $50\%$.

Answer: $50\%$ of them will be carriers.