Question

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

Answer 1

Answer:

GUA and GUG.

Explanation:

If you look at the attached genetic code, the wild-type glutamic acid (Glu) is coded by the codons GAA and GAG.

Valine (Val) can be coded by the codons GUU, GUC, GUA or GUG.

Sickle-cell hemoglobin arises from a single mutation, which causes the translation of Val instead of Glu. The only codons that code for Valine that differ in just one base with the Glu codons are GUA and GUG.