Abstract: Human leukocyte antigen (HLA)- G defects can result in the occrence of preeclampsia, in this paper, In order to clarify the role of HLA - G and its single nucleotide polymorphisms(SNPs) in preeclampsia furtherly，we detected the correlation between HLA-G SNPs and preeclampsia in pregnancy women of Chinese Han population in Tianjin. Objective: To detect the distribution of HLA-G SNPs which is one of the susceptibility genes of preeclampsia in severe preeclampsia patients and normal pregnant women, to understand the change of HLA-G SNPs in the patients with severe preeclampsia. Method: The blood samples were collected from 67 cases of severe preeclampsia group and 37 cases of control group, the genomic DNA of samples were extracted, the Exon-2 and Exon-3 of HLA-G SNPs were chosen to evaluate through sequencing, the fluorescent primers were synthesized and PCR was proceeded, the fragments obtained from PCR were sequenced and analyzed to find SNPs, The correlation of SNPs and severe preeclampsia was analyzed by statistical analysis. Results: Two SNPs, C374T and G476A were found in the Exon 2 of HLA-G. Three SNPs, C810T, C859A and G954A were found in Exon 3. There was no significant difference in the distribution of the SNPs between preeclamptic and normal pregnancies. Conclusions：1. Five SNPs (C374T, G476A, C810T, C859A and G954A) were found in the HLA-G Exon 2 and 3, which were not related to severe preeclampsia, these SNPs were synonymous mutations. 2. C374T and G954A were newly discovered HLA-G SNPs which were submitted to the dbSNP and obtained NCBI Assay Id (ss#) 119994701 and 119994702, and the Reference SNP Id (rs#): rs77474325 and rs75783850.

Key words: Preeclampsia, HLA - G, Gene, Exon, Single nucleotide polymorphisms