What's GAG, GUG, and beta globin chain?
A point mutation results in replacement of GAG by GUG at the sixth position in the beta globin chain of the hemoglobin. This results in the replacement of glutamic acid with valine and causes decrease in elasticity leading to improper folding of the hemoglobin molecule. This causes the RBC's to become sickle shaped and results in sickle cell anemia.