[Gene typing of merozoite surface protein 1 of Plasmodium falciparum isolates from Hainan Province].

Objective: To identify the genotype of merozoite surface protein 1 (MSP1) of Plasmodium falciparum isolates from Hainan Province.
Methods: Nested PCR was applied to amplify the MSP1 of Blocks 2 and 3 Plasmodium falciparum isolates from Hainan Province. Two allelic family representative gene fragments were sequenced.
Results: From 36 out of 39 blood samples from Plasmodium falciparum patients, 44 gene fragments of blocks 2 and 3 of the MSP1 were amplified, of which the MAD20-type allele was dominant(75%). followed by K1-type allele. No RO33-type allele was found. The mixed infection rate of the two different allelic type was 19.4%. Sequence analysis showed that the sequences of MAD20- and K1-type isolates from Hainan Province were highly homologous to that of the MAD20 and K1 allelic prototypes.
Conclusion: Two principal allelic types of MSP1 gene, MAD20- and K1-type, exist in malaria endemic areas in Hainan Province, the MAD20-type being the dominant.