摘要目的:了解河北省保定市经男男同性性行为（men who have sex with men，MSM）途径感染HIV-1（human immunodeficiency virus type 1，HIV-1）的患者中，HIV-1亚型分布和分子传播网络情况。方法:使用In-house方法扩增HIV-1 pol区目的基因序列，通过系统进化分析和HIV-1耐药数据库比对确定基因型和基因变异情况，并利用TN93模型计算pol序列基因距离，构建HIV-1分子网络。结果:CRF01_AE是最主要HIV-1毒株亚型，构成比为51.9%（94/181），其次是CRF07_BC26.5%（48/181）、B亚型14.4%（26/181）和CRF103_01B2.8%（5/181），其它近年来新鉴定的流行重组毒株占4.4%（8/181）；原发耐药率为8.3%（15/181）；共有50条序列进入HIV-1分子网络，入网率为27.6%（50/181），共鉴别出17个传播簇，其中最大的一簇是CRF01_AE，共有36个节点。结论:河北省保定地区通过MSM途径感染HIV-1的人群中HIV-1亚型复杂多样，耐药率处于中等水平，加强耐药监测和防控措施，并对重点传播簇进行干预，对控制该地区疫情发展具有重要意义。

abstractsObjective:To investigate the subtypes distribution and molecular transmission network of human immunodeficiency virus type 1 (HIV-1) among patients infected via the route of men who have sex with men (MSM) in Baoding city, Hebei province.Methods:In-house method was used to amplify the target sequence in pol region of HIV-1. Genotyping and mutations were analyzed by phylogenetic analysis and alignments to HIV-1 drug resistance database. The TN93 model was used to calculate genetic distance of pol gene and construct HIV-1 molecular transmission network. Results:The CRF01_AE was the predominant subtype, with a constitutive ratio of 51.9% (94/181), followed by CRF07_BC (26.5%, 48/181), subtype B (14.4%, 26/181) and CRF103_01B (2.8%, 5/181). Other prevalent recombinant strains newly identified in recent years accounted for 4.4% (8/181). The prevalence of primary HIV-1 drug resistance was 8.3% (15/181). A total of 50 sequences were included in the HIV-1 molecular transmission network, with a network access rate of 27.6% (50/181). A total of 17 transmission clusters were identified and the largest cluster was CRF01_AE cluster with a total of 36 nodes.Conclusions:HIV-1 subtypes among patients infected by MSM route in Baoding city were complicate and diverse with medium level of drug resistance rate. Enhanced drug resistance surveillance, prevention and control measures and intervention for key transmission clusters would be valuable for the epidemic control in this area.