Association of the maternal 14-bp insertion/deletion polymorphism in the histocompatibility leukocyte antigen G gene with recurrent implantation failure

BACKGROUND Implantation failure of blastocyst is one of the main reasons of failure to become pregnancy following use of Assisted Reproductive Techniques. HLA-G, one of the non-classic HLA subtypes, seems to have a vital role in neutralizing of mother immune system. According to importance of ins/del polymorphism of HLA-G in regulation of HLA-G expression, it seems that this polymorphism has an important effect in immune response against embryo, and so success of embryo implantation. OBJECTIVE In this experiment we try to evaluate association of HLA-G ins/del polymorphism with risk of occurrence of RIF in ART treated infertile women. MATERIALS AND METHODS To evaluating insertion/deletion polymorphism association with RIF we design a case-control study. We select 40 women with history of recurrent failure to become pregnant following IVF as RIF case group. Forty women with pregnancy following IVF were selected as control. Members of both groups were assessed to rule out of anatomical, immunological and known genetical cause of infertility. Presence of 14 bp insertion/deletion alleles was assessed using PCR-PAGE technique. The data were analyzed by means of SPSS software using Chi-Square tests at the significant level of p<0.05. RESULTS Our data shows that frequency of heterozygote genotype (ins/del) was significantly higher in case group. Furthermore presence of HLA-G insertion/deletion genotype shows association with increase of implantation failure risk by 3.85 fold. CONCLUSION According our results, Heterozygote genotype of ins/del leads to increase of RIF risk. It seems that by genotyping of HLA-G polymorphism, we can predict risk of implantation failure in infertile women after use of ART.