HLA class II polymorphisms and recurrent spontaneous abortion in a Southern Brazilian cohort

Cumulative Evidence for Association of IL-10 -1082G > A Polymorphism with Susceptibility to Recurrent Pregnancy Loss: A Systematic Review and Meta-Analysis

The IL-10 -1082 G > A polymorphism has been reported to be associated with a risk of recurrent pregnancy loss (RPL) with inconsistent results. Thus, to clarify the effect of the polymorphism on the susceptibility to RPL, a meta-analysis was performed. Methods: A systematic literature search in PubMed, Web of Science, Scopus and SciELO was performed to identify the relevant studies published up to December 20, 2019, and related information was extracted. Results: A total of 17 case-control studies with 3,224 RPL cases and 3,295 controls were selected. Pooled data revealed that IL-10 -1082 G > A polymorphism was significantly associated with risk of RPL in the global population. Moreover, subgroup analysis indicated a significant association in Caucasians, but not in Asian or mixed populations. Conclusions: Our pooled data highlights that IL-10 -1082 G > A polymorphism is a risk factor for RPL susceptibility in the global population, especially in Caucasians.

Maternal HLA-DR, HLA-DQ, and HLA-DP loci are linked with altered risk of recurrent pregnancy loss in Lebanese women: A case-control study

PROBLEM

We investigated the association between idiopathic recurrent pregnancy loss (RPL) and HLA-DPB1, HLA-DQB1, and HLA-DRB1 alleles and DPB1-DQB1-DRB1 haplotypes.

METHOD OF STUDY

Case-control retrospective study involved 93 Lebanese women with unexplained RPL, and 113 multiparous Lebanese women with two or more successful pregnancies, and no miscarriages who served as controls. DPB1, DQB1, and DRB1 genotyping was performed by PCR-SSP.

RESULTS

Expected and observed DRB1, DQB1, and DPB1 frequencies were comparable, and HLA genotype frequencies were in Hardy-Weinberg equilibrium. Significantly higher frequencies of DRB1*04:01:01 and DRB1*08:01:01, and decreased DRB1*07:01:01 frequency were seen in RPL cases than in controls. On the other hand, the distribution of DQB1 alleles was comparable between cases and control groups. Significantly lower frequencies of DPB1*04:01:01 and DPB1*14:01:01 were seen in women with RPL than control subjects. While the frequency DPB1*02:01:01 was markedly higher in RPL cases than in controls, the difference was not significant. DPB1-DQB1-DRB1 haplotype analysis identified haplotype DPB1*04:01:01-DQB1*03:02:01-DRB1*04:01:01 to be positively associated, while haplotype DPB1*04:01:01-DQB1*02:01:01-DRB1*07:01:01 to be negatively associated with RPL. Of these two haplotypes, only DPB1*04:01:01-DQB1*02:01:01-DRB1*07:01:01 remained significant after correction for multiple tests (P_c  = .0008).

CONCLUSION

Our results confirm an association of select DRB1 and DPB1 alleles with RPL in Lebanese women, and the first to identify DPB1-DQB1-DRB1 linked with altered RPL susceptibility, further highlighting the immunological/inflammatory nature of RPL.

Association of Tumor Necrosis Factor-α (TNF-α) -308G>A and -238G>A Polymorphisms with Recurrent Pregnancy Loss Risk: A Meta-Analysis

Background

Multiple studies have been carried out examining the association of tumor necrosis factor-α gene (TNF-α) promoter region polymorphisms with recurrent pregnancy loss (RPL) risk. However, the results remain controversial and incomplete. Hence, we performed a meta-analysis to evaluate the association of the TNF-α -308G>A and -238G>A polymorphisms with RPL risk.

Materials and Methods

In this meta-analysis, a comprehensive search of PubMed, Web of Knowledge and EMBASE was performed to identify relevant studies published until December 1, 2017. The associations were assessed by odds ratio (OR) and its corresponding 95% confidence interval (CI).

Results

A total of 29 case-control studies, comprising 20 studies on TNF-α -308G>A (3,461 cases and 3,895 controls) and nine studies on TNF-α -238G>A (2,589 cases and 2,664 controls), were included in the meta-analysis. Overall, we found TNF-α -308G>A to be associated with an increase in RPL risk under the homozygote (OR=1.716, 95% CI: 1.210-2.433, P=0.002) and the recessive (OR=1.554, 95% CI: 1.100-2.196, P=0.012) models. TNF-α -238G>A was also significantly associated with increased risk of RPL under the allele model (OR=1.554, 95% CI: 1.100-2.196, P=0.012). Stratified analysis revealed a more significant association between theTNF-α -308G>A polymorphism and increased RPL risk in Asians under the homozygote (OR=2.190, 95% CI: 1.465-3.274, P≤0.001), the dominant (OR=1.642, 95% CI: 1.269-2.125, P≤0.001) and the recessive (OR=1.456, 95% CI: 1.039-2.040, P=0.029) models, but not in Caucasians. A non-significant association was, however, identified between TNF-α -238G>A and RPL risk based on ethnicity. Moreover, TNF-α -308G>A and -238G>A polymorphisms were significantly associated with increased risk of RPL in high quality studies and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) subgroups.

Conclusion

The present meta-analysis demonstrates that TNF-α -308G>A and -238G>A polymorphisms are associated with an increased risk of RPL.

No Association between TNF-α -308G/A Polymorphism and Idiopathic Recurrent Miscarriage: A Systematic Review with Meta-Analysis and Trial Sequential Analysis

Background

Conflicting results were reported on the association between the TNF-α -308G/A polymorphism and idiopathic recurrent miscarriage (IRM). Though three meta-analyses have been conducted on this topic, the conclusions were contradictory, and the results may be unreliable as certain crucial conditions were neglected.

Method

A complete search was conducted in PubMed, Cochrane Library, and Embase, other sources like Google Scholar, ClinicalTrial.gov and reference lists of relevant articles were also retrieved. All candidate articles were accessed and screened using specific inclusion and exclusion criteria. Statistical analyses were performed on data extracted from eligible studies using the STATA 12.0 software and the TSA 0.9 beta software.

Results

Eventually, 12 case-control studies from 11 publications (with 1,807 cases and 2,012 controls) were included in this meta-analysis, and no evidence of any significant association was found in the overall analyses between the TNF-α -308G/A polymorphism and IRM risk. However, significant association was shown in Asian population (four studies from three publications) in the dominant model (AA + GA vs. GG), the allelic model (A vs. G), and the heterozygote model (GA vs. GG).

Conclusions

TNF-α -308G/A polymorphism is not associated with IRM risk. Though significant association was found in Asian population, the result needs further confirmation from more studies.

Association of TNF-α genetic polymorphisms with recurrent pregnancy loss risk: a systematic review and meta-analysis

BACKGROUND

Several studies on the association of tumor necrosis factor alpha (TNF-α) polymorphisms with recurrent pregnancy loss (RPL) risk have reported conflicting results. The present meta-analysis was conducted to provide a more precise estimation of these relationships and to investigate the real association between TNF-α polymorphisms and RPL.

METHODS

An extensive eligible literature search for relevant studies was conducted on PubMed, Embase, and The Cochrane Library from their inceptions to May 12, 2015. Specific inclusion criteria were used to evaluate articles. The odds ratio (OR) with 95% confidence intervals (CIs) were used to assess the strength of associations. Statistical analyses were performed by the STATA12.0 software.

RESULTS

10 case-control studies including 1430 RPL patients and 1727 healthy controls were identified. Meta-analysis indicated that TNF-α-308G/A (rs1800629) polymorphism in the TNF-α gene correlated with elevated RPL risk whereas no significant association was observed between TNF-α-238G/A (rs361625) and RPL.

CONCLUSIONS

The current meta-analysis demonstrates that TNF-α-308G/A polymorphism in the TNF-α gene is associated with susceptibility to RPL.