Hereditary spherocytosis is due to...................... deficiency ?

Ans. is 'a' i.e., SpectrinHereditary spherocytosis (HS) o Hereditary spherocytosis is an inherited disorder, caused by intrinsic defects in red cell membrane that is characterized by the production of red cell that are sphere shaped rather than biconcave donut- shaped, and therefore are sequestrated in spleen and destroyed there.Structural defect in Hereditary spherocytosiso Membrane cytoskeleton that lies closely opposed to the internal surface of the plasma membrane, is responsible for elasticity and maintenance of RBC shape.o Membrane skeleton consists : ?1. Spectrin -> The chief protein component.2. Ankyrin and band 4.2 --> Binds spectrin to band 33. Band 3 --> A transmembrane ion transpo protein.4. Band 4.1 --> Binds spectrin to glycophorin A, a transmembrane protein. o Hereditary spherocytosis is caused by a variety of molecular defects in genes that code for any of the following :- Ankyrin --> Most common Band 3 Second most common Spectrin Band 4.2o Hereditary spherocytosis is acquired as autosomal dominant in majority of the cases. In some cases autosomal recessive pattern of inheritence is seen.