关键词: 间日疟原虫, 膜蛋白质类, 聚合酶链反应, 限制性片段长度多态性, 等位基因

Abstract: Objective To develop a method for detecting the genotype of Plasmodium vivax merozoite surface protein 1 (PvMSP-1) alleles. Methods According to the sequence characteristic of PvMSP-1, nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to amplify the polymorphic region of ICB5-ICB6 which contains Q repeats and PvuII restriction site (Sal-1 type). The PCR product was digested by PvuII restriction endonuclease and the digested fragments were observed by 2% agarose gel electrophoresis. The allelic type was determined according to the banding pattern. Results Bands in size of 400 bp (Belem type ) and/or 470 bp (Sal-1 type ) appeared in all 98 P. vivax isolates, no band was found in negative control. After PvuII digestion, two Sal-1 type fragments (120 bp and 350 bp) were obtained from 45 samples of 470 bp. Single-band of 400 bp appeared in 3 of 40 samples with 400 bp as Belem type, two bands of 120 bp and 280 bp appeared from other 35 samples as recombination type III, and another 2 bands with 120 bp and 240 bp as Korean isolate. Conclusion The result showed that the nested PCR-RFLP may be applied in the detection and identification of the three PvMSP-1 allelic types in China.

Key words: Plasmodium vivax, membrane proteins, polymerase chain reaction, restriction fragment length polymorphism, alleles