Question

Explain the molecular basis for the complications that arise from sickle-cell anemia.

Answer 1

Major complications which occurs in sickle cell anemia is a anemic condition.persons which differs from anemia do not have sufficient red blood cells, so have less oxygen and always feel tiredness and fatigue. Other major complications are

- Pale yellow colour of skin

- Jaundice

- Shortness of breathing

- Chest pain

MOLECULAR BASIS

Sickle cell anemia is a autosomal recessive disease.

In sickle cell anemia, hemoglobin S(an unknown subunite) replaces both beta globin subunite in heamoglobin.

Main reason for such changes are Mutation.

Mutation occurs in single nucleotide of beta globin gene, which results in glutamic acid replaced by valine at position 6.

HeamoglobinS with this mutation referred to as Hbs. When Hbs polymerizes itself then low oxygen condition occurs.

The heterogygou Hbs did not show any problem, because normal allele produce half normal heamoglobin.

Homozygous Hbs show changes in shape of RBCs and make it fragile.

Carriers shows symptoms only when they did not get sufficient oxygen and while they severely dehydrated.