Polymorphism of HLA-D QA1 alleles in Chinese Han patients with persistent Chlamydia trachomatis genital infection

Objective To analyze the association of HLA-DQA1 gene polymorphism with persistent Chlamydia trachomatis genital infection.Methods Blood samples were collected from 80 patients with persistent genital Chlamydial infection,80 patients with common genital Chlamydial infection (who tested negative for Chlamydia trachomatis after one course of standard systemic treatment) and 80 normal human controls.HLA-DQA1 alleles were genotyped by PCR followed by gene sequencing.Results The frequency of HLA-DQA1*0102 allele and HLA-DQA1*0501 allele was 22.5％ and 5.0％ respectively in patients with persistent genital Chlamydial infection,5％ and 20％ respectively in those with common genital Chlamydial infection,2.5％ and 17.5％ respectively in normal human controls.Compared with the patients with common genital Chlamydial infection and controls,the patients with persistent genital Chlamydial infection had a higher frequency of HLA-DQA1*0102 (x2 =14.6286,P ＜ 0.001 ),but a lower frequency of DQA1*0501 (x2 =6.2598,P ＜ 0.05).Conclusions HLA-DQA1*0102 allele may be a susceptible gene or closely linked with the susceptible genes of persistent genital Chlamydial infection.HLA-DQA1*0501 allele may have protective effects against persistent genital Chlamydial infection.