Hemoglobin is a complex protein that contains four polypeptide chains. The normal hemoglobin found in adults, called adult hemoglobin, consists of two alpha and two beta polypeptide chains, which are encoded by different loci. Sickle-cell hemoglobin, which causes sickle-coil anemia, arises from a single mutation in the beta chain of adult hemoglobin. Adult hemoglobin and sickle-cell hemoglobin differ in a single amino add. The sixth amino acid from one end in adult hemoglobin is glutamic acid, whereas sickle-cell hemoglobin has valine at this position. After consulting a codon table, indicate the mutant codons that could give rise to sickle-cell anemia.
GUC
GAA
GUG
GUA
GAG
Indicate the type of mutation that gave rise to sickle-cell anemia.
a frameshift that results from a two-base deletion
a transversion that leads to a nonsense mutation
a transition that leads to a missense mutation
a transversion that leads to a missense mutation
a transition that leads to a neutral mutation