中文摘要：

目的初步了解云南临沧HIV阳性者血液中弓形虫的基因型特征。方法运用巢式PCR法对弓形虫SAG2基因的两个片段分别进行基因提取、扩增，然后对PCR产物进行回收纯化、酶切及测序，并与弓形虫基因I型标准株进行对比鉴定。结果从170份HIV阳性者全血样本中分别扩增出35个弓形虫SAG2基因（241、221bp），从其中扩增阳性的全血样本中各选择4份分别进行酶切，扩增出目的基因片殷，进一步从酶切样本中选择2份与弓形虫基因标准株RH株进行对比，酶切SAG2基因（241bp）显示血液样本基因型为I型或Ⅱ型，酶切SAG2基因（221bp）确定基因型均为I型。结论初步确定云南临沧HIV阳性者弓形虫基因型以I型为主。

英文摘要：

Objective To preliminarily understand the genotype characteristics of Toxoplasma gondii in blood of HIV-posi- tive persons in Lineang City, Yunnan Province. Method Two segments of SAG2 gene of T. gondii from blood samples of HIV- positive persons in Lincang City were extracted and amplified by using the nested PCR method and the genotype was identified and compared with the standard strain （Type I） of Toxoplasma gondii. Results Thirty-five SAG2 genes （241 bp） and 35 SAG2 genes （221 bp） of T. gondii were amplified from 170 blood samples of the HIV-positive people, and 4 of each case were selected and digested with enzyme, then 2 aim gene fragments of each case were chosen and compared with the standard strain （Type I） of T. gondii. The digestion of SAG2 gene （241 bp） showed the genotype of the blood samples was Type I or Type II, and the digestion of SAG2 gene （221 bp） confirmed that the genotype was Type I. Conclusion It is preliminarily confirmed that the genotype of T. gondii in blood of HIV-positive persons in Lincang City, Yunnan Province is Type I.