PLASMODIUM-FALCIPARUM - TYPING OF MALARIA PARASITES BASED ON POLYMORPHISM OF A NOVEL MULTIGENE FAMILY

Pf60.1, a marker recently isolated from the human malaria parasite Pla smodium falciparum, defines a large multigene family encoding antigens of 60 kDa, expressed by the blood stages (Carcy et al., Molecular and Biochemical Parasitology, 1994, 68, 221-233). Southern blotting showe d that DNA from all strains and field isolates analyzed contained a la rge number of Pf60.1 copies. Considerable RFLP was observed. This dive rsity could be likewise visualized by analyzing PCR fragments amplifie d using primers derived from the Pf60.1 insert. Specific, multiple-ban d pat terns were generated from laboratory strains, cloned lines, or w ild isolates. This was further outlined after RsaI digestion of the PC R products. The sensitivity of this amplification was such that produc ts could be visualized using a DNA amount representing less than one g enome equivalent. Moreover, amplification was observed in some strains using a single primer, suggesting that some members of the Pf60.1 fam ily are adjacent in an inverted orientation. This analysis confirmed t he genetic similarity of a subset of laboratory strains. The results d escribed here show that the extended diversity of this P. falciparum g ene family provides a useful and sensitive PCR approach for strain typ ing. (C) 1995 Academic Press, Inc.