RESUMO
<p><b>OBJECTIVE</b>To assess the association of human leukocyte antigen DQ gene polymorphisms with unexplained recurrent spontaneous abortion (URSA) among ethnic Han Chinese from Wenzhou region.</p><p><b>METHODS</b>Fifty couples with URSA (URSA group) and 66 couples with normal pregnancy history (control group) were recruited. The alleles of HLA-DQA1 and HLA-DQB1 were analyzed by polymerase chain reaction with specific sequence primers (PCR-SSP) in all subjects. The frequency distribution of HLA-DQ alleles, odds ratios (OR) between each group and sharing of HLA-DQ alleles were calculated.</p><p><b>RESULTS</b>The frequency distribution of HLA-DQB1*03:03 allele in the females with URSA was significantly higher than that healthy females (21.00% vs. 9.85%, OR=2.433, 95%CI: 1.232-4.894, χ(2)=5.657, P<0.05). The HLA-DQB1*05:03 allele was present among the healthy females with a frequency of 3.03%, and was not detected among females with URSA. For both males and females, the HLA-DQB1*05:02 allele were only typed in control group with frequencies of 6.06% and 5.30%, respectively. The sharing of HLA-DQA1 alleles in couples with URSA was increased compared with the control group (70.27% vs. 44.64%, OR=2.931, 95%CI: 1.216-7.067, P<0.05).</p><p><b>CONCLUSION</b>The increased sharing of HLA-DQA1 alleles may contribute to the susceptibility of URSA among ethnic Han Chinese from Wenzhou region. The allele of HLA-DQB1*03:03 in the females may be predisposing factor for URSA. However, the HLA-DQB1*05:02 allele in both gender and HLA-DQB1*05:03 allele in females may confer a protective effect.</p>
