A missense mutation causes sickle cell disease by
A)altering the protein's shape and affecting its function.
B)changing a triplet codon that does not affect the reading frame.
C)altering an intron splicing site so that an entire exon is deleted.
D)substituting beta globin chains with alpha globin chains.

Question

Quizplus · Accepted Answer

A missense mutation involves a single nucleotide change, which results in a different amino acid being incorporated into the protein sequence. In sickle cell disease, a missense mutation in the beta-globin gene causes the substitution of valine for glutamic acid at position 6 of the beta-globin chain. This alters the protein's shape, making it less soluble and leading to the characteristic sickle shape of red blood cells. This change in shape affects the protein's function, leading to the symptoms of sickle cell disease.

A Missense Mutation Causes Sickle Cell Disease by