Association of adiponectin gene variants with idiopathic recurrent miscarriage according to obesity status: a case-control study.

BACKGROUND: This study addresses whether the association of adiponectin gene (ADIPOQ) variants with idiopathic recurrent pregnancy loss (RPL) is influenced by obesity. METHODS: Retrospective case-control study performed in outpatient obstetrics/gynecology clinics. Study subjects comprised 308 women with RPL, defined as ≥ 3 consecutive miscarriages of unknown etiology, and 310 control women. ADIPOQ genotyping was done by allele exclusion method on real-time PCR. RESULTS: Of the 14 ADIPOQ variants tested, the minor allele frequency (MAF) of rs4632532, rs17300539, rs266729, rs182052, rs16861209, and rs7649121 were significantly higher, while rs2241767, and rs1063539 MAF were lower in RPL cases, hence assigning RPL-susceptibility and protection to these variants, respectively. Higher frequencies of heterozygous rs17300539 and rs16861209, and homozygous rs4632532, rs266729, and rs182052 genotypes, and reduced frequencies of heterozygous rs1063539 and rs2241767, homozygous rs2241766 genotypes were seen in RPL cases. ADIPOQ rs4632532, and rs2241766 were associated with RPL in obese, while rs1063539 and rs16861209 were associated with RPL in non-obese women; rs182052 and rs7649121 associated with RPL independently of BMI changes. Based on LD pattern, two haplotype blocks were identified. Within Block 1 containing rs4632532, rs16861194, rs17300539, rs266729, rs182052, rs16861209, rs822396, and rs7649121, increased frequency of CAGGACAT and TAACGAAA, and reduced frequency of TAGCGCAA haplotypes were seen in RPL cases when compared to controls, thereby assigning RPL susceptibility and protection, respectively. CONCLUSION: This is the first study to document contribution of ADIPOQ variants and haplotypes with RPL, and also to underscore the contribution of obesity to genetic association studies.

Contribution of JAK2 and STAT3 variants to the genetic susceptibility of recurrent miscarriage among Bahraini and Tunisian Arabs.

We investigated the contribution of JAK2 rs2203724 and STAT3 rs1053023 and rs1053004 to the susceptibility of idiopathic recurrent miscarriage (IRM) in Bahraini (246 cases and 279 controls) and Tunisian (235 cases and 235 controls) Arabs. The distribution of JAK2 rs2203724 and STAT3 rs1053023 genotypes were in Hardy-Weinberg equilibrium (HWE) in both communities, while mild deviation from HWE was noted for rs1053004 in Tunisians but not Bahraini. JAK2 rs2203724 was not associated with IRM in either community, while STAT3 rs1053023 was positively associated with IRM in both Bahraini and Tunisian women. STAT3 rs1053004 displayed mixed association: it was positively associated with IRM in Bahraini (P < 0.001), but not Tunisian women (P = 0.10). Genotype association confirmed the association of both STAT3 variants with IRM under additive, dominant, and recessive models, while the association of STAT3 rs1053023 was seen under additive and dominant, but not recessive models in Tunisians. The contribution of JAK2 and STAT3 variants to IRM susceptibility must be evaluated regarding specific variants, and the ethnic/racial background.

Contribution of JAK2 and STAT3 variants to the genetic susceptibility of recurrent spontaneous miscarriage in a Tunisian population.

AIMS: Th1 and Th2 balance is crucial for maintenance of pregnancy, and intracellular JAK and STAT proteins significantly contribute to it. In view of evidence linking JAK2 and STAT3 variants with recurrent spontaneous miscarriage (RSM), here we investigated the association of JAK2 (rs2230724) and STAT3 (rs1053023 and rs1053004) to RSM susceptibility in Tunisians. SUBJECTS AND METHODS: A retrospective case-control study. Subjects comprised 235 RSM cases and 235 control subjects. JAK2 and STAT3 were genotyped by the allelic discrimination method. RESULTS: STAT3 rs1053023 and, to a lower extent, rs1053004 were significantly associated with RSM under the additive and dominant, but not recessive models. This remained significant after adjustment for the covariates age, smoking, and gravida. In contrast to STAT3 variants, JAK2 rs2230724 was not associated with RSM under any of the genetic models tested. Two-locus STAT3 (rs1053023/rs1053004) haplotype analysis revealed increased frequency of the C/G haplotype in patients with RSM. Multivariate regression analysis confirmed the association of C/G haplotype with RSM (p=0.001; odds ratio=2.01; 95% confidence interval=1.32-3.07), thus conferring RSM susceptibility nature. These differences remained significant after applying the Bonferroni correction for multiple testing (Pc=0.004). CONCLUSIONS: STAT3 rs1053023, more so than the STAT3 rs1053004 or JAK2 rs2230724 polymorphisms, is associated with RSM risk.

Endothelial protein C receptor 1651C/G polymorphism and soluble endothelial protein C receptor levels in women with idiopathic recurrent miscarriage.

High levels of soluble endothelial protein C receptor (EPCR) induce coagulation dysfunction by inhibiting protein C activation, and activated protein C (APC) activity. We tested whether EPCR 1651C/G promoter variant and changes in plasma soluble EPCR levels are risk factors for idiopathic recurrent spontaneous miscarriage (RSM). A case-control study involving 283 RSM cases and 380 age and BMI-matched control women. EPCR 1651C/G genotyping was performed by PCR-RFLP method. Plasma-soluble EPCR levels were measured with ELISA. The 1651G allele frequency and C/G genotype were significantly higher in RSM cases than controls; none of the cases or control participants was a 1651G/G homozygote. Lower soluble EPCR levels were seen in RSM cases compared to controls, and higher soluble EPCR levels were seen in 1651C/G compared to 1651C/C carriers in cases and controls. Lower soluble EPCR levels were seen in cases, both in 1651C/C (P = 0.0046) and 1651C/G (P = 0.0032) genotype carriers. Multivariate analysis demonstrated strong association of EPCR 1651C/G [P = 0.011; adjusted odds ratio (aOR) (95% confidence interval [CI] = 3.13 (1.31-7.60)], but not soluble EPCR plasma levels [P = 0.067; aOR (95% CI) = 1.01 (1.00-1.10)], with increased RSM risk. In addition, smoking was independently associated with increased RSM risk [P = 0.002; aOR (95% CI) = 2.86 (1.48-5.52)]. EPCR 1651C/G polymorphism and elevated soluble EPCR levels but low soluble EPCR levels increase the risk of idiopathic RSM. Replication studies on other racial groups, and other EPCR gene variants, are warranted.

Common polymorphisms in the P-selectin gene in women with recurrent spontaneous abortions.

BACKGROUND: To investigate possible associations of P-selectin polymorphisms with idiopathic recurrent pregnancy loss (RPL). METHODS: Study subjects comprised 270 consecutive RPL cases attending outpatient maternity services, and 322 multi-parous control women. P-selectin genotyping was done by PCR-RFLP and PCR-ASA methods. RESULTS: The P-selectin variants rs1800807, rs1800805, and rs6127, were in Hardy Weinberg equilibrium, and low linkage disequilibrium was noted between the three studied SNPs. The frequency of rs6127 A allele (P<0.001I), but not rs1800807 C allele (P=0.957) or rs1800805 A allele (P=0.760), was higher in RPL cases than in control women. Significant differences in the distribution of rs6127 (P<0.001), but not rs1800807 (P=0.444) or rs1800805 (P=0.391) genotypes were seen between cases and controls, and only rs6127 showed a significant association with RPL, with increments of 2.65 and 4.96 in disease risk seen for heterozygous and homozygous carriers, respectively. Among the 8 three-locus Pselectin haplotypes constructed (rs1800807/rs1800805/rs6127), increased frequency of GGG (Pc=0.0249), CGG (Pc=0.0256), and CAG (Pc=0.0174) haplotypes, and lower frequency of CGA haplotype (Pc=0.0091) were seen in RPL cases, thus conferring disease susceptibility and protective nature to these haplotypes, respectively. CONCLUSIONS: P-selectin gene polymorphisms and haplotypes contribute to RPL development.

Genetic variations in the interleukin-21 gene and the risk of recurrent idiopathic spontaneous miscarriage.

OBJECTIVES: Insofar as recurrent spontaneous miscarriage (RSM) is linked with dysregulated immunity and inflammatory changes, and given the pro-inflammatory role of interleukin-21 (IL-21), we examined the association between IL-21 polymorphisms and RSM. METHODS AND RESULTS: IL-21 rs2055979, rs13143866, rs9992580, and rs4833837 were genotyped in 235 cases of RSM and 235 controls. Regression analysis was employed in assessing the contribution of IL-21 variants to the overall RSM risk. Higher minor allele and genotype frequencies of rs2055979 and rs13143866, but not rs9992580 or rs4833837, were seen in RSM patients than in the controls. IL-21 haplotype [rs9992580/rs4833837/rs2055979/rs13143866] analysis revealed a lower frequency of the TGCG haplotype, and a higher frequency of the GGCG and GAAA haplotypes in patients, thus conferring protection from or a susceptibility to RSM by these haplotypes respectively. Regression analysis confirmed the association of TGCG [OR (95%CI)=0.09 (0.05-0.16)], and GGCG [OR (95%CI)=2.52 (1.34-4.54)] and GAAA [OR (95%CI)=4.02 (2.20-7.70)] haplotypes, after adjusting for age and BMI. CONCLUSIONS: Our findings indicate that IL-21 is a novel susceptibility gene for RSM.