Question

Sickle-cell anaemia results due to mutation caused by

• A. substitution
• B. insertion
• C. deletion
• D. duplication

Answer 1

Answer: (A)

Sickle-cell anaemia is an autosomal recessive disorder that occurs due to the substitution of glutamate by valine at position- $6$ of haemoglobin- $\beta$ -chain. It occurs due to the point mutation of nucleotide $A$ to $T$ in the codon for amino acid $6$ that changed glutamic acid codon $(GAG)$ to valine codon $(GTG)$.