Question

Many different types of mutations can occur within the body. Sickle cell anemia is a disease that occurs when a mutation in a base pair of the hemoglobin beta gene causes a single replacement of the amino acid glutamic acid by the amino acid valine. As a result of this mutation, the individual’s blood cells take on a sickle shape under certain conditions and form clusters that can block blood vessels and cause organ damage. mc017-1.jpg mc017-2.jpg Which type of mutation causes sickle cell anemia?

Answer 1

A point mutation causes sickle cell anemia. This is a single change in the 6th codon from the start of the HBB gene (codes for the beta-globin subunit).
Normally the 6th codon is for glutamic acid (codon is GAG)...but the point mutation happens at the A .... changing this codon to GUG ...which codes for Valine...
Turns out to be a very seriously bad single point mutation (17 nucleotides from the start of the gene).

Answer 2

the answer is B missense