中文摘要：

目的鉴定中国四川蓝氏贾第鞭毛虫（简称贾笫虫）C2株的型特异性基因，为其基因分型提供依据。方法根据GenBank中收录的贾第虫基因序列，选取贾第虫WB株的2个型特异性基凶和GS株的5个型特异性基因，设计引物，以C2株基因组DNA为模板，进行PCR反应。从中选取一个没有PCR产物的基因设计外同引物（该引物预期能扩增出此基因的侧翼序列和其相邻基因的部分序列），再次进行PCR反应。将纯化的PCR产物克隆至pMD19-T载体并测序。型特异性基斟的缺失通过对其相邻片段的扩增验证。结果从中国四川贾第虫C2株基因组DNA中成功扩增出贾第虫WB株的2个型特异性皋出GL50803—3386和GL50803～4447，扩增片段长度分别为1586bp和1080bp，并证实其缺失1个贾第虫GS株的型特异性基因GL50581—2613。结论中国四川贾第虫C2株可能属于贾第虫WB株。

英文摘要：

Objectives To identify genotype-specific genes in the Giardia lamblia C2 strain isolated from Sichuan, China and provide a reference for genotyping of the C2 strain. Methods Genotyp-specific genes of 2 Giardia WB strains and 5 GS strains were selected; primers were designed according to their reference sequences in GenBank. These genes were amplified with PCR using genomic DNA of the （22 strain as a template. One of the genes that could not he amplified was chosen to design outer primers, which were expected to amplify the flanking sequences and portions of adjacent genes, The amplification products were then cloned into the vector pMD19 T and sequenced. The lack of a genotype-spe cific gene was confirmed by amplifying adjacent fragments. Results Two genes specific to WB were amplified from genomic DNA of the C2 strain. The amplification products of GL50803_3386 and GL50808_4417 were 1 586 hp and 1 080 bp, respectivcly. The lack of 2 613, a gene specific to GS, was confirmed. Conclusion The C2 strain may be a WB strain of Giardia.