Allelic forms of the knob associated histidine-rich protein gene of Plasmodium falciparum.

The knob associated histidine-rich protein (KAHRP) gene was cloned and sequenced from two Indian isolates of Plasmodium falciparum, Pf3-92 and Pf29-92. These isolates showed major sequence differences in the C-terminal repeat domain of KAHRP. However, the biologically important domains such as spectrin-actin binding region remained highly conserved. The PCR amplification of a variable C-terminal repeat domain from the clinical isolates of P. falciparum, from Rajasthan epidemic, showed the presence of multiple alleles of KAHRP gene. The presence of multiple alleles indicates the existence of several P. falciparum strains in India. This should be taken into account for future malaria control strategies such as molecular therapy and vaccines.