Question

Sickle cell anaemia disorder arises due to

• A. duplication of a segment of DNA
• B. substitution of a single base pair of DNA
• C. deletion of a segment of DNA
• D. duplication of a base pair of RNA

Answer 1

The correct option is B substitution of a single base pair of DNA

Sicke cell anaemia is an autosomal recessive genetic disorder. In this genetic disorder, valine is synthesized in place of glutamic acid at sixth position of $\beta$ globin chain of haemoglobin. Due to the change in the structure of haemoglobin, the RBC's become sickle shaped. This genetic disorder is due to substitution of a single base pair of DNA. This type of change in DNA is called point mutation.