Which of the statements are correct about Thalassemia?
A. In \(β\) Thalassemia, production of \(α\) globin chain is affected and in \(α\) Thalassemia production of \(β\) globin chain is affected.
B. \(α\) Thalassemia is controlled by two closely linked genes HBA1 and HBA2.
C. The genes HBA1 and HBA2 are located on chromosome 11 of each parent.
D. \(β\) Thalassemia is controlled by a single gene HBB.
E. The gene HBB is located on chromosome 16 of each parent.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → B and D only
A. In \(\beta\) Thalassemia, production of \(\alpha\) globin chain is affected and in \(\alpha\) Thalassemia production of \(\beta\) globin chain is affected. — False. It is the other way round.
B. \(\alpha\) Thalassemia is controlled by two closely linked genes HBA1 and HBA2. — True.
C. The genes HBA1 and HBA2 are located on chromosome 11 of each parent. — False. They are on chromosome 16.
D. \(\beta\) Thalassemia is controlled by a single gene HBB. — True.
E. The gene HBB is located on chromosome 16 of each parent. — False. HBB is on chromosome 11.
NCERT Extract:
Mendelian Disorders – “… In α Thalassemia, production of α globin chain is affected while in β Thalassemia, production of β globin chain is affected. 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 alpha globin molecules produced. While 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.”