[Cloning and sequence analysis of the gene encoding the second region of MSA1 from three Chinese isolates of Plasmodium falciparum].

Gene encoding the second region of merozoite surface antigen (MSA1-R2) of three Chinese isolates of Plasmodium falciparum from Hainan, Yunnan and Anhui were amplified by PCR, cloned into M13 and sequenced. Comparison among MSA1-R2 sequences from different isolates of P. falciparum shows that there is no difference among the three Chinese isolates. The sequence of MSA1-R2 of the Chinese isolates are highly homologous with that of WELLCOME from West Africa. The sequence flanking the upstream of the tandem repeats is exactly the same as that of MAD-20, but sequence downstream the repeats exhibit the characteristics of K1 allele, indicating that intragenic recombination of the two MSA1 allelic families exists in the Chinese isolates.