Sickle cell trait patient do not have manifestations as that of Sickle cell disease, because?

Ans. is 'a' i.e., 50% Hbs is required for occurence of sickling Sickle cell disease occurs in following forms 1. Heterozygous state, i.e., sickle cell trait. 2. Homozygous state, i.e., sickle cell anemia. o The most impoant factor for sickling is the amount of HbS in the cell. o In sickle cell trait (heterozygous state), only about 40% of the hemoglobin is HbS, this is insufficient to produce sickling manifestations. o In homozygous state, almost all the hemoglobin in the red cell is HbS, therefore they undergo sickling.