The genetic condition resulting from a point mutation in the hemoglobin gene leading to sickle-shaped red blood cells is: MCQ with Answer and Explanation

The genetic condition resulting from a point mutation in the hemoglobin gene leading to sickle-shaped red blood cells is:
A. Hemophilia
B. Thalassemia
C. Sickle cell anemia
D. Cystic fibrosis
Answer: Option C
Solution (By JKSSB Mock Tests)
Sickle cell anemia is an autosomal recessive disorder caused by a single nucleotide substitution (GAG → GTG) in the β-globin gene, resulting in glutamic acid replaced by valine, producing abnormal hemoglobin S. Under low oxygen, HbS polymerizes, distorting RBCs into sickle shape, causing pain and organ damage.

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Correct Answer: Option C


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