Sickle cell anaemia is caused by which kind of mutation?
Answer and explanation
Correct answer: C. A point substitution that replaces glutamic acid with valine in beta-globin
- Step 1: A single base change alters one codon in the beta-globin gene. Step 2. This puts valine where glutamic acid belongs, which makes haemoglobin polymerise. Answer: A point substitution that replaces glutamic acid with valine in beta-globin. Why not the others: Deletion, frameshift and translocation describe other mutation types.
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