Botanyα-thalassemia is controlled by ___(i)___ gene present on ___(ii)___ chromosome. (i)(ii)1.HBA1 and HBA2162.HBB113.HBB164.HBB and HBA211

$α$ -thalassemia is controlled by _(i)_ gene present on _(ii)_ chromosome.
(i) (ii)
1. HBA1 and HBA2 16
2. HBB 11
3. HBB 16
4. HBB and HBA2 11

Solution:

$α$ thalassemia is controlled by two closely linked genes HBA1 and HBA2 on chromosome 16 of each parent and it is observed due to mutation or deletion of one or more of the four genes. The more genes affected, the less $α$ globin molecules produced. $β$ Thalassemia is controlled by a single gene HBB on chromosome 11 of each parent and occurs due to mutation of one or both the genes.