Abstract: AIM:Determining nucleotide sequence of the circumsporozoite protein partial gene of
the Plasmodium falciparum PFD-3/YN(Yunnan of China)and finding out the differences of the CS
gene sequence between Chinese Plasmodium falciparum isolate and other isolates.METHODS:The
circumsporozoite protein gene fragment was amplified by polymerase chain reaction and cloned
into M13 bacteriophage.M13 CSP single strand DNAs of the three positive clones were extracted
respectively.Then,the nucleotide sequence of the CS gene ragment was determined by the dideoxy chain termination method. PCGENE software was used to compare and analyze the CS gene sequence of the six isolates. RESULTS:Different degrees of diversity of the CS gene sequences were found among P. falciparum PFD - 3/YN and other isolates (T4,Wellcome,NF54, 3D7 and 7G8). A non-silent substitution at the nucleotide level being found in the P. f Th/Tc antigenic epitope region. CONCLUSION: There were differences in the CS gene sequence among P. falciparum PFD- 3/YN and those of other isolates.

Key words: Plasmodium falciparum, circumsporozoite protein gene, gene sequencing