question_answer 19)

  Which of the following statements is the most appropriate for sickle-cell anaemia? (a) It cannot be treated with iron supplements (b) It is a molecular disease (c) It confers resistance to acquiring malaria (d) All of the above

Answer:

                    (d) Sickle-cell anaemia is an autosome linked recessive trait. In this genetic disorder point mutation in p-globin chain results in change of glutamate (glutamic acid) to valine at sixth position. Only the homozygous individuals for,i.e.,  show the diseased phenotype. The heterozygous individuals are carriers. It is also known that heterozygotes, having both types of haemoglobin, show resistance to malaria infection because the body targets the P. falciparum (protozoan) infected cells for destruction of RBC.