Q. Sickle cell anaemia is due to the mutation of

 1811  234 COMEDKCOMEDK 2009Principles of Inheritance and Variation Report Error

Solution:

Sickle cell anaemia is an autosomal hereditary 'disorder in which erythrocytes become sickle shaped. There is formation of· an abnormal haemoglobin called haemoglobin- S. This disorder is caused by the substitution of glutamic acid (glu) by valine (val) at the sixth position of the beta glcibin chain of the haemoglobin molecule due to a point mutation which changes codon CTC (glu)toCAC (val) on DNA and causes change of GAG toGUG in.resulting mRNA.