Why are people with sickle-cell anaemia less likely to get malaria?

lorriem1222

The sickle-cell trait protects them from Malaria. Kinda like an antibody. http://www.cdc.gov/Features/Sicklecell/ Apr 02 08, 4:45 PM

zbeckabee

People with sickle cell disease can get malaria just like anyone else. However, people with sickle cell trait are less likely to get malaria. The trait doesn't completely protect a person from infection, but it makes death from malaria less likely. It so happens that in areas where there is a high incidence of the sickle cell anaemia allele, there is also a high incidence of malaria. The parasite that causes malaria infects the red blood cells and multiplies within them. People who are heterozygous for sickle cell anaemia are much less likely to get the potentially lethal malaria than those who have 2 copies of the normal allele. There is a strong selection pressure against homozygous sicklers because they can become seriously anaemic. There is a strong selection pressure against homozygous normal haemoglobin alleles in malarial areas because these individuals are more likely to contract malaria. Therefore, in malarial areas, there is a strong advantage to be a carrier for the sickle cell disease. http://www.s-cool.co.uk/topic_quicklearn.asp?loc=ql&topic_id=5&quicklearn_id=5&subject_id=3&ebt=69&ebn=&ebs=&ebl=&elc=13 http://www.cdc.gov/Features/SickleCell/ Apr 02 08, 4:47 PM

triviapaul

Normally, the malaria parasite uses the red blood cell to reproduce. "Within the red blood cells the parasites multiply further, again asexually, periodically breaking out of their hosts to invade fresh red blood cells." Sickle cells make reproduction impossible for parasites. "The malaria parasite has a complex life cycle and spends part of it in red blood cells. In a carrier, the presence of the malaria parasite causes the red blood cell to rupture, making the plasmodium unable to reproduce. Further, the polymerization of Hb affects the ability of the parasite to digest Hb in the first place." http://en.wikipedia.org/wiki/Malaria#Mosquito_vectors_and_the_Plasmodium_life_cycle http://en.wikipedia.org/wiki/Plasmodium http://en.wikipedia.org/wiki/Sickle-cell_disease Apr 02 08, 5:08 PM