9700/12 Biology Feb Mar 2020 Online Test | Cambridge AS and A Level MCQ
Sickle cell anaemia is caused by a mutation in an allele of the gene that codes for the $\beta $-globin polypeptide of haemoglobin.
The diagram shows the sequence of bases in a small section of the coding strand of DNA for both the HbA (normal) and HbS (sickle cell) $\beta $-globin alleles.
HbA CTGACTCCTGAGGAGAAGTCT
HbS CTGACTCCTGTGGAGAAGTCT
How will the mutation in the HbS allele result in the production of an altered…