Given below are the two peptide chains of red blood cells. Identify the correct option:
 

	A	B
1.	HbA peptide	HbS peptide
2.	HbA peptide	Normal peptide
3.	Abnormal peptide	HbA peptide
4.	HbS peptide	HbA peptide

The mutation in the sixth position of β globin gene changes an amino acid in the HBB protein from glutamic acid to valine. Due to this single nucleotide variation, β globin chains get misshapen. The accumulation of such defective haemoglobin molecules (HbS) inside the RBCs distorts the shape of the RBCs. As a result, RBCs acquire the shape of a sickle, thereby causing Sickle Cell Anemia.

In figure A, there is glutamine in the sixth position and in figure B, there is valine at sixth position. Therefore, A represents the HbA peptide and B represents the HbS peptide.