Genetics of parasitic infections

Parasites cause much suffering mainly in countries of the southern hemisphe re. Hundreds of millions of individuals are infected by schistosomes, leish manias, plasmodiums, trypanosomes, and various other parasites, and severe clinical disease occurs in a sizable fraction of the infected population ca using death and severe sequelae. The outcome, asymptomatic, subclinical or clinical disease, of an infection depends mostly on the parasite and on its host. Several groups analyzing the genetics of human susceptibility to par asites have began to identify the critical steps of the pathogenic mechanis ms in a few parasitic infections such as malaria and schistosomiasis. The p resent article, which is not meant to be an exhaustive review of the field, illustrates the progresses made in this field from pioneer studies in anim als to works in endemic populations using modern strategies of human geneti cs.