Question

Using the genetic code shown here, predict what type of mutation has occurred in the hemoglobin sickle cell anemia allele

Normal allele 5'-GGAAUGAAACAGGAACCC-3
Mutant allele 5-GGAAUGAAACAGGUACCC-3

a. a point mutation. Val to Glu
b. a frameshift mutation
c. addition of a new stop codon
d. a point mutation.

Answer 1

The mutation in the hemoglobin allele for sickle cell anemia is a point mutation, leading to the specific change of glutamic acid to valine, which is a missense mutation affecting hemoglobin structure and function.

Step-by-step explanation:

The student is asking about the type of mutation present in the sickle cell anemia allele. After examining both the normal and mutant alleles for hemoglobin, we can determine that there is a change in a single nucleotide. This alteration is a substitution of adenine (A) by thymine (T), which changes the codon GAG to GTG. This specific change results in the amino acid glutamic acid being replaced by valine at the sixth position of the beta chain of hemoglobin.

The correct classification of this genetic alteration is a point mutation, which is known as a missense mutation. It is so named because the mutation causes one amino acid to be replaced by another within the protein sequence, potentially impacting the protein's function.

In conclusion, the type of mutation displayed in the hemoglobin sickle cell anemia allele is a single base change or point mutation, leading to a critical amino acid substitution from glutamic acid to valine (Val to Glu).