Question

If both the parents are carriers for thalassaemia, the chances of an afflicted child to be born to them is:

• A. 25\%
• B. 50\%
• C. 75\%
• D. 100\%

Hint:

In autosomal recessive disorders, both parents must contribute a defective allele for the child to be affected.

Answer 1

The Correct Option is A

Thalassaemia is an autosomal recessive disorder. If both parents are carriers (\(Tt\)): \[ \text{Punnett Square:} \begin{array}{c|c|c} & T & t
\hline T & TT & Tt
\hline t & Tt & tt
\end{array} \] The possible genotypes are: \(TT\): Normal (25\%) \(Tt\): Carrier (50\%) \(tt\): Afflicted (25\%)