Question

Which of the following statements are CORRECT?
Statement (I): Thalassemia is an autosomal, inherited recessive disease.
Statement (II): Haemoglobin molecule is made up of four polypeptide chain - \(2\alpha\) and \(2\beta\) chains
Statement (III): The synthesis of \(\alpha\)-chain are controlled by HBA 1 and HBA2 on chromosome 11
Statement (IV): The synthesis of \(\beta\) chain is controlled by single gene (HBB) on chromosome 16.

• A. All statements are correct
• B. All statements are incorrect
• C. Statement (I) and (II) are correct while (III) and (IV) are incorrect
• D. Statement (III) and (IV) are correct while (I) and (II) are incorrect

Hint:

Recall the nature of thalassemia and which chromosomes carry the alpha and beta globin genes. The chromosome numbers in two statements are swapped.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
Thalassemia is an autosomal recessive blood disorder caused by reduced synthesis of globin chains.
Haemoglobin has four chains, two alpha and two beta.

Step 2: Check statements I and II
Statement I is correct as thalassemia is autosomal and recessive.
Statement II is correct as haemoglobin has \(2\alpha\) and \(2\beta\) chains.

Step 3: Check statements III and IV
The alpha chain genes HBA1 and HBA2 lie on chromosome 16, not 11.
The beta chain gene HBB lies on chromosome 11, not 16.
So III and IV are incorrect.

Step 4: Conclusion
I and II are correct while III and IV are incorrect.

Final Answer:
Statements I and II are correct and III and IV are incorrect. \[ \boxed{\text{(C) }\text{Statement (I) and (II) are correct while (III) and (IV) are incorrect}} \]