This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
In sickle cell anaemia, the defect can be explained as having arisen from 
Select and explain. 
A. A base insertion in DNA, B. A base deletion in DNA, C. A base substitution in DNA, D. None of the above
C: A base substitution in DNA
Answer: C: A base substitution in DNA 
Explanation: Sickle cell anaemia is caused by a point mutation (i.e. a base substition).