Risk Of Recurrent Pregnancy Loss Research Articles

MiR604A>G gene polymorphism is associated with recurrent pregnancy loss in Turkish women.

Recurrent pregnancy loss is considerably a reproductive health problem for couples. Genetic, epigenetic, and environmental factors play an important role in the development of recurrent pregnancy loss. While there are many causes, genetic and epigenetic factors are common. Inthis study, we aimed to examine the association between miR604 (rs2368393) A>G gene polymorphism and the risk of recurrent miscarriage in the Turkish population. The study included 250 participants (i.e., 150 patients and 100 controls). DNA samples were isolated from peripheral blood, and polymerase chain reactions and restriction fragment length polymorphism methodologies were applied. The genotype distribution and allele frequencies of miR604A>G gene showed statistically significant differences between patients and control groups (p=0.002 and p<0.002, respectively). As a result of the study, we found that the AA genotype and A allele of the miR604A>G gene were statistically significant for the risk of recurrent pregnancy loss in Turkish women.

Эндотелиальная дисфункция при привычном невынашивании беременности: генетические факторы и факторы внешней среды

Objective. To examine the association between the carriage of endothelial dysfunction-related gene polymorphisms and recurrent pregnancy loss (RPL). Patients and methods. This case-control study included 87 patients who were divided into two groups. The study group consisted of 65 patients with a history of two or more consecutive pregnancy losses (2 to 11 losses). Primary RPL was detected in 20 patients, secondary in 26, and tertiary in 19. The control group consisted of 22 women with a history of three or more full-term births without episodes of miscarriage. The frequency of polymorphisms of the VEGFA -634G&gt;C and IL6 -174G&gt;C genes was determined by a ready-to-use real-time polymerase chain reaction (RT-PCR) test kits. Results. Carrying the VEGFA -634G&gt;C GC genotype increases the risk of RPL 4-fold (p = 0.0072) and the IL6 -174G&gt;C GC genotype – 3-fold (p = 0.028). Analysis of the impact of combinations of unfavorable genotypes showed that 65.0% of patients with primary RPL, 61.5% with secondary RPL, 63.2% with tertiary RPL, and 9% of healthy controls had a combination of GC VEGFA -634G&gt;C and CC IL6 -174G&gt;C. One of the key environmental factors determining the realization of susceptibility genes is age: the maximum age at the time of the first intended pregnancy was observed in patients with primary RPL (32.6 years vs. 25.5 years in the control group; p &lt; 0.05), with 9% of healthy controls having a combination of two genotypes associated with pregnancy loss. That is, successful pregnancy at a younger age is possible even when carrying multiple risk alleles. The birth interval length is also important for successful pregnancy: a short inter-pregnancy interval allows to carry out the reproductive function during the most favorable period of the reproductive system before the influence of genotypes predisposing to RPL begins. Other environmental factors leading to the realization of carriage of RPL risk alleles include a history of intrauterine interventions and sexually transmitted infections. Conclusion. Study of the VEGFA -634G&gt;C and IL6 -174G&gt;C gene polymorphisms may serve as an effective method to predict RPL. For patients carrying these unfavorable gene polymorphisms, it is especially important to perform the reproductive function in time, i.e., before the realization of environmental factors. Key words: recurrent pregnancy loss, VEGF, endothelial dysfunction, susceptibility genes

Association of CYP11A1 Polymorphisms with Recurrent Pregnancy Loss in the Female Population of Punjab.

Recurrent pregnancy loss (RPL) is defined as the failure of two or more clinically recognised pregnancies before 20 weeks of gestation. The prevalence of clinically evident RPL is 1%-2% worldwide. The aetiologies of RPL include uterine anatomic anomalies, uncontrolled diabetes mellitus, untreated hypothyroidism, parental chromosomal abnormalities, antiphospholipid antibody syndrome, thrombophilia, genetic abnormalities and infections. This study was aimed at investigating the possible association between CYP11A1 (rs11632698) and (rs4077582) polymorphisms with RPL in the female population of Punjab. The case- control study was conducted on 170 subjects, of which 80 RPL cases and 90 controls were analysed. Genotypic analysis was performed using the polymerase chain reaction - restriction fragment length polymorphism. Pearson's Chi-square test was used. The genotypic frequency of CYP11A1 (rs11632698) A > G polymorphism was statistically significantly different amongst cases and controls (P = 0.00001). It was observed that the presence of the G allele might increase the risk of RPL. A Chisquare analysis of CYP11A1 (rs4077582) (P = 0.01) indicated a significant difference amongst the genotypes of cases and controls of RPL. CYP11A1 variants (rs11632698 and rs4077582) may be useful markers in determining the genetic susceptibility to the pathogenesis of RPL. Keywords: CYP11A1, recurrent miscarriage, recurrent pregnancy loss, rs11632698, rs4077582, spontaneous abortion.

Celiac Disease Predisposition and Genital Tract Microbiota in Women Affected by Recurrent Pregnancy Loss.

The incidence of Idiopathic Recurrent Pregnancy Loss (RPL) is doubled in patients suffering from Celiac Disease (CD) compared to healthy populations. CD genetic components are HLA class II genes known as HLA-DQ2 and DQ8. Genetically susceptible women can remain asymptomatic even though they are exposed to a doubled risk of RPL compared to the general population. Furthermore, CD has been associated with microbiota alterations. The aim of this study is to evaluate endometrial and vaginal microbiota in HLA-DQ2/DQ8 positive and negative RPL patients compared to healthy pregnant women. Endometrial and vaginal microbiota of 3 subgroups were evaluated: 15 HLA-DQ2/DQ8 positive RPL women, 25 HLA DQ2/DQ8 negative RPL women (for a total of 40 RPL women) and 7 healthy fertile controls with previous uncomplicated pregnancies (all HLA-DQ2/DQ8 negative). The 2 RPL subgroups (HLA-DQ2/DQ8 positive and negative) showed a different endometrial and vaginal composition in the Lactobacillacae family compared to controls: Lactobacillus acidophilus was absent both in the vaginal and endometrial samples of RPL women, while Lactobaciluus iners, which can favor a less stable vaginal microbiota, was found only in RPL women (26.4% in HLA DQ2/DQ8 positive and 22.1% HLA DQ2/DQ8 negative) in both the vaginal and endometrial districts. In conclusion, both HLA DQ2/DQ8 positive-RPL and HLA DQ2/DQ8 negative-RPL women showed different endometrial and vaginal microbiota composition compared to healthy controls.

Maternal ApoE genotype and risk of recurrent pregnancy loss: An updated systematic review and meta-analysis.

In order to clarify the role of the maternal apolipoprotein E (ApoE) genotype and the risk of recurrent pregnancy loss (RPL), we herein performed an updated systematic review and meta-analysis to reevaluate the evidence on this association. A comprehensive literature search was performed on PubMed, Web of Knowledge and the Cochrane library up to September 2022. Methodological study quality was assessed using the Newcastle-Ottawa Scale and the credibility of significant pooled odds ratios (ORs) was estimated by the false positive report probability and the Bayesian false discovery probability. Twelve studies published from 2009 to 2022 fulfilled the inclusion criteria. In the overall analysis, the ε4 allele was found to confer an increased risk of RPL compared to the ε3 allele (OR 1.60, 95% CI 1.00-2.55, p = 0.049) and women carrying the ApoE ε4 allele displayed a higher risk of RPL compared with those carrying the ε2 and ε3 alleles (OR 1.75, 95% CI 1.06-2.87, p = 0.028). Subgroup analysis based on subjects' ethnicity revealed that these associations were restricted to the Asian population (ε4 allele vs. ε3 allele, OR 5.93, 95% CI 1.79-19.61, p = 0.004; ε4 allele carriers vs. carriers of ε2 and ε3 alleles, OR 8.42, 95% CI 1.47-48.12, p = 0.017). None of the associations detected were found to be noteworthy under false positive report probability or Bayesian false discovery probability at a prior probability of 0.001. This updated meta-analysis highlights an association between maternal ApoE genotype and RPL risk in Asians, but not in Caucasians. Further case-control studies are warranted in women of Asian ancestry to exclude the possibility of false-positive findings.

The association of gene polymorphisms related to inherited thrombophilia with an increased risk of recurrent pregnancy loss

The association of gene polymorphisms related to inherited thrombophilia with an increased risk of recurrent pregnancy loss

Association of Polymorphisms in the Long Non-Coding RNA HOTAIR with Recurrent Pregnancy Loss in a Korean Population.

Recurrent pregnancy loss (RPL) affects 1% to 5% of women, with devastating effects on both reproductive health and psychological well-being. Homeobox (HOX) transcript antisense RNA (HOTAIR) is a long non-coding RNA (lncRNA) produced by HOXC; it plays a major role in invasion and development of ovarian and other cancers. The aim of the present study was to analyze effects of HOTAIR polymorphisms (rs4759314 A>G, rs920778 T>C, rs1899663 G>T, and rs7958904 G>C) on RPL in Korean women. A total of 403 women with RPL and 383 healthy women were selected for this study. Genotyping analysis was performed with the polymerase chain reaction, restriction fragment length polymorphism, and the TaqMan genotyping assay. Clinical characteristics were compared using Student's unpaired t-test and the chi-square test for categorical variables. Logistic regression was performed to evaluate associations between single nucleotide polymorphisms and RPL incidence. In all assays, p < 0.05 was considered significant. HOTAIR polymorphisms rs4759314A>G and rs920778T>C were highly associated with increased risk of RPL, specifically the haplotypes rs4759314A>G/rs1899663G>T (G-T) and rs4759314A>G/rs920778 T>C (G-C). These associations were maintained in haplotypes that contained three polymorphisms (rs4759314 A>G, rs920778 T>C, and rs1899663 G>T) A-C-G, G-T-G, and G-T-T, further indicating that the HOTAIR rs4759314 and rs920778 polymorphisms play significant roles in idiopathic RPL in Korean women.

A Systematic Review and Meta-Analysis of the Association between the FV H1299R Variant and the Risk of Recurrent Pregnancy Loss.

This study evaluated the association between the H1299R factor V (FV) variant (rs1800595) and recurrent pregnancy loss (RPL). Pubmed (MEDLINE) and Embase (OVID) bibliographic databases were searched from the inception to 31 May 2022 to identify suitable articles according to PRISMA and MOOSE guidelines. We included observational studies, case-control studies, cross-sectional studies, and cohort studies reporting a numerical and well-distinguished Het or Hom status of the H1299R variant obtained through PCR or other biochemical techniques and comparing RPL patients with a healthy control group. The review protocol was registered at PROSPERO (CRD42022330077). Two authors independently screened studies, extracted data, and carried out the risk of bias assessment using the Newcastle Ottawa scale (NOS). A meta-analysis was performed with RevMan software Version 5.4 using an odds ratio (OR) with an M-H, random effect, and 95% CI. We included 13 clinical studies for a total of 1669 RPL patients and 1466 healthy women as a control group. H1299R variant was slightly associated with RPL albeit without significance (OR 1.18, 95% CI: 0.78-1.80, p = 0.44). Subgroup analyses considering H1299R in heterozygosity (OR 1.13, 95% CI: 0.76-1.67, p = 0.56) and in homozygosity (OR: 2.11, 95% CI: 0.74-6.01, p = 0.16) revealed a similar trend. Lastly, we evaluated the association between H1299R and RPL based on the number of previous miscarriages (≥2 or ≥3). This comprehensive systematic review and meta-analysis sheds light on the specific influence of the H1299R variant in the F5 gene on RPL, constituting valid support for medical care during pregnancy and genetic counseling.

Investigation of the role of X chromosome inactivation and androgen receptor CAG repeat polymorphisms in patients with recurrent pregnancy loss: a prospective case–control study

BackgroundPrevious research has revealed that skewed X chromosome inactivation (SXCI) and androgen receptor (AR) CAG polymorphisms are associated with increased risk of recurrent pregnancy loss (RPL); however, the results are conflicting, and the underlying mechanisms remain unclear. This study investigated the role of SXCI and AR CAG polymorphisms in patients with RPL and explored whether the underlying mechanisms were related to the ovarian reserve and preimplantation embryo aneuploidy.MethodsThis was a prospective case-control study carried out in a tertiary hospital-based reproductive medicine center. An external validation RPL cohort was recruited during the study period. Data on baseline and cycle characteristics were collected. X-chromosome inactivation (XCI) was measured using a human AR assay. AR polymorphisms were assessed using quantitative fluorescent polymerase chain reactions and direct sequencing. Blastocysts of the patients with RPL were tested by single nucleotide polymorphism microarray based preimplantation genetic testing for aneuploidy.ResultsIn total, 131 patients with idiopathic RPL and 126 controls were included for the case-control study. Patients with RPL exhibited a significantly more skewed XCI distribution pattern (67.71 ± 10.50 vs. 64.22 ± 10.62, p = 0.011), as well as significantly shorter bi-allelic mean (18.56 ± 1.97 vs. 19.34 ± 2.38, p = 0.005) and X-weighted bi-allelic mean (18.46 ± 2.02 vs. 19.38 ± 2.53, p = 0.001) of AR CAG repeats. Multivariate logistic regression models indicated that CAG repeat < 20, SXCI, and duration of stimulation were independently associated with the risk of RPL. However, SXCI and AR CAG polymorphisms were not associated with ovarian reserve or preimplantation embryo aneuploidy in the RPL group, and the same results were attained in a separate validation cohort of 363 patients with RPL.ConclusionSXCI and AR CAG polymorphisms are related to RPL; however, these two factors do not lead to RPL by affecting the ovarian reserve or increasing embryo aneuploidy. The roles of SXCI and AR CAG in RPL may involve other mechanisms that require further investigation.Trial registration:NCT02504281, https://www.clinicaltrials.gov (Date of registration, 21/07/2015; date of enrolment of the first subject, 30/07/2015).

ASSOCIATION OF MIR -149 T>C AND MIR-27aA>G GENE POLYMORPHISMS WITH RECURRENT PREGNANCY LOSS RISK IN GREEK POPULATION

Are miR -149 T>C AND miR-27aA>G gene polymorphisms associated with recurrent pregnancy loss risk in Greek population?

Genetic Variations miR-10aA>T, miR-30cA>G, miR-181aT>C, and miR-499bA>G and the Risk of Recurrent Pregnancy Loss in Korean Women

This study investigated the genetic association between recurrent pregnancy loss (RPL) and microRNA (miRNA) polymorphisms in miR-10aA>T, miR-30cA>G, miR-181aT>C, and miR-499bA>G in Korean women. Blood samples were collected from 381 RPL patients and 281 control participants, and genotyping of miR-10aA>T, miR-30cA>G, miR-181aT>C, and miR-499bA>G was carried out by TaqMan miRNA RT-Real Time polymerase chain reaction (PCR). Four polymorphisms were identified, including miR-10aA>T, miR-30cA>G, miR-181aT>C, and miR-499bA>G. MiR-10a dominant model (AA vs. AT + TT) and miR-499bGG genotypes were associated with increased RPL risk (adjusted odds ratio [AOR] = 1.520, 95% confidence interval [CI] = 1.038–2.227, p = 0.032; AOR = 2.956, 95% CI = 1.168–7.482, p = 0.022, respectively). Additionally, both miR-499 dominant (AA vs. AG + GG) and recessive (AA + AG vs. GG) models were significantly associated with increased RPL risk (AOR = 1.465, 95% CI = 1.062–2.020, p = 0.020; AOR = 2.677, 95% CI = 1.066–6.725, p = 0.036, respectively). We further propose that miR-10aA>T, miR-30cA>G, and miR-499bA>G polymorphisms effects could contribute to RPL and should be considered during RPL patient evaluation.

Cumulative risk assessment of phthalates exposure for recurrent pregnancy loss in reproductive-aged women population using multiple hazard indices approaches

Background and aim: Phthalates, which are commonly used in flexible plastics and consumer products, have been reported to be toxic to reproductive and developmental function in mammals. Past studies have focused on the toxic effects on male reproduction, with only a few studies conducted on the risks that cumulative exposure to phthalates have on the female reproductive system. Methods: We recruited 260 patients with recurrent pregnancy loss (RPL) of unknown etiology and 203 controls from the clinics of Obstetrics and Gynecology at a medical center in southern Taiwan from 2013 to 2020. The daily intake of phthalates was estimated from urine samples using the back-calculation method, after which the cumulative risk was determined using multiple hazard indices, including a dose-addition model, a receptor effect model, and a hazard index approach. Results: The patients with RPL had a significantly higher cumulative exposure to phthalates (p &amp;#x3c; 0.05) than did the controls with a hazard index above one. After adjusted logistic regression analysis, we found that the risk of RPL was strongly related to the higher quartiles of DEHP, the DEHPTEQ for the antiandrogenic effect and adverse effects of the female reproductive system and the ERα binding effect (p &amp;#x3c; 0.05). Conclusions: Our work suggests that more attentions should be paid to the adverse effects induced by phthalates on female reproduction, especially the effects caused by the cumulative exposure to phthalates in women of reproductive age. Keywords: Phthalates; Cumulative risk assessment; Relative potency factor; Recurrent pregnancy loss

Polymorphisms of ACE and thrombophilic genes: risk for recurrent pregnancy loss

BackgroundRecurrent pregnancy loss (RPL) affects up to 5% of pregnancies, but with no consensus on the definition. Inherited thrombophilia has been postulated as a risk factor for RPL. The aim...

Role of CYP1A1, CYP2D6, and NOS3 gene polymorphisms in idiopathic recurrent pregnancy loss in the Iranian Azeri population: A case-control study.

Background It is estimated that 1-5% of couples suffer from recurrent pregnancy loss (RPL). Recent studies have shown the effects of gene polymorphisms in RPL.ObjectiveThe aim of this study was to evaluate 3 gene polymorphisms including rs1048943 of CYP1A1, rs28371725 of CYP2D6, and rs7830 of NOS3 in idiopathic RPL to identify their association with RPL.Materials and MethodsBlood samples were collected from 136 women with at least 2 consecutive idiopathic miscarriages (case group) and 136 women with no history of miscarriage and at least one successful pregnancy (control group) from the Iranian Azeri population. This study was carried out between April 2018-April 2020. Amplification-refractory mutation system polymerase chain reaction was used for the rs7830, rs1048943 and rs28371725 polymorphisms in order to genotype each extracted genomic DNA sample. After that, Chi-square, Fisher's exact test and logistic regression were used to investigate whether each of these polymorphisms is associated with RPL.ResultsAmong these polymorphisms, only rs1048943 of CYP1A1 showed a statistically significant association with RPL in the Iranian Azeri women studied.ConclusionOur results suggest that CYP1A1 gene polymorphisms might be associated with a reduced risk of RPL. Further studies in other populations and in the same population with a larger sample size, as well as functional genomics analyses such as gene expression analyses or epigenetic studies are required to validate our results.

Association of the IL-6 gene rs1800796 polymorphism with recurrent pregnancy loss in a population of women from northwestern China: a case-control study

We aimed to identify whether IL-1β (rs1143627, rs1143634 and rs16944), IL-6 (rs1800796), IL-10(rs1800872 and rs1800896), and vascular endothelial growth factor (VEGF) (rs1570360) gene polymorphisms were risk factors for recurrent pregnancy loss (RPL) in a population of women in northwestern China. A total of 150 women with a history of two or more unexplained and consecutive spontaneous abortions before their 24th gestational week and 150 age-matched women with at least two normal pregnancies and no history of pregnancy loss were included in the present study as cases and controls, respectively. We extracted genomic DNA from peripheral blood, and executed genotyping with the SNaPshot technique. Logistic regression analysis was conducted to determine the odds ratios (ORs) of the associations between the polymorphisms and RPL. Of the seven polymorphisms we studied, only IL-6 rs1800796 showed a statistically significant association with RPL, as we noted an elevated risk of RPL with the G allele (OR = 1.57; 95% CI, 1.10–2.24; p = .01). The risk of RPL in women with the GG + CG genotype (OR = 1.96; 95% CI, 1.19–3.21; p = .01) was also higher than that in women with the CC genotype. The present study thus indicated that the IL-6 gene rs1800796 polymorphism may serve as an important risk factor for RPL in this group of women from northwestern China. IMPACT STATEMENT What is already known on this subject? Cytokine and vascular endothelial growth factor (VEGF) gene polymorphisms may affect the risk of recurrent pregnancy loss (RPL) by modulating cytokine and VEGF expression. What do the results of this study add? The study results showed that the IL-6 rs1800796 single-nucleotide polymorphism constituted a risk factor for RPL in a population of women in northwestern China. What are the implications of these findings for clinical practice and/or further research? This study clearly reflects clinical significance as it provides a theoretical basis for the early screening of RPL by revealing that the IL-6 gene rs1800796 polymorphism increased the risk of RPL in women in northwestern China.

Maternal Thrombophilic and Hypofibrinolytic Genetic Variants in Idiopathic Recurrent Pregnancy Loss: a Continuing Mystery.

Despite the fact that multiple recurrent pregnancy loss (RPL) etiologies have been identified, 50-70% of RPL cases remain enigmatic, and idiopathic RPL is still a serious medical challenge. A plethora of studies have investigated the correlation of RPL with variations in coagulation and/or fibrinolytic factors-encoding genes. Notwithstanding, evidence for a link between these variations and RPL remains discordant. We aimed to explore the association of thrombophilic and hypofibrinolytic gene variations with RPL development. Two hundred Saudi women were recruited in this study, comprising 150 women experiencing RPL and 50 healthy women. Thirteen genetic variants, including FV G1691A, FV A4070G, F2 G20210A, F13A1 G103T, FGB - 455G > A, PAI-1 - 675 4G/5G, ITGB3 T1565C, MTHFR C677T, MTHFR A1298C, ACE I/D, APOB G10708A, APOE T388C, and APOE C526T were genotyped using ViennaLab StripAssay. Women experiencing RPL harbor significantly higher frequencies of the F13A1 103T, FGB - 455A, and ITGB3 1565C alleles than control women (p < 0.001). No differences in the prevalence of other investigated variants were identified between control women and those with RPL. No considerable link of F5 1691G > A/4070A > G, MTHFR 677C > T/1298A > C, and APOE 388T > C/526C > T haplotypes with RPL risk was demonstrated. F13A1 G103T, FGB - 455G > A, and ITGB3 T1565C variants are connected to a higher likelihood of developing RPL and, hence, may have the potential to identify those women at risk of RPL, thereby, improving RPL susceptibility prediction. Incorporating molecular testing of thrombophilic and hypofibrinolytic genetic variants into routine workup could confer a promising approach for refined RPL risk assessment.

Molecular investigation of association between common IL-6 polymorphism with cytomegalovirus (CMV) infection and recurrent miscarriage in Iranian women.

Recurrent pregnancy loss (RPL) is described as two or more spontaneous abortions. To date, scientists in various fields of knowledge, such as genetics, endocrinology, anatomy, immunology, and microbiology, have identified some important factors that affect abortions; nonetheless, the precise basic etiology is not determined in up to 50% of RPL cases. Human cytomegalovirus (CMV) infection and host genetic background, like IL-6 SNP polymorphisms, play important roles in RPL etiology. This study aimed to evaluate the relationships among single nucleotide polymorphisms (-634C/G and -174 G/C) in the IL-6 gene with CMV infection and the risk of RPL for early detection and treatment. This case-control study was carried on 80 Iranian females with RPL and 80 healthy females as controls. DNA was extracted from samples and CMV and IL6 SNPs were detected using Tetra ARMS-PCR. Statistics were analyzed by Epi Info TM and SPSS software by X2 test for the roles of CMV detection and two polymorphisms in RPL. The results indicated an increased rate of CMV infection in the RPL group (44%) compared to the control group (25.45%). The prevalence of IL-6-634C/G genotype among RPL patients with CMV infection was 80%, while the frequency of this genotype among RPL patients without CMV infection was 50%. Furthermore, no substantial relation was found between IL-6-174 G/C genotypes and RPL (p = 0.005). This study not only indicated a significant role for CMV in RPL, but also showed an association between CMV and allele G in IL6-634 among Iranian women. In addition, the findings suggested the use of CMV and IL-6-634 GG genotypes as diagnostic and prognostic biomarkers for RPL in the Iranian population.

Study of association between different microRNA variants and the risk of idiopathic recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a common reproductive disorder among women and a major cause of infertility among them; however, the underlying causes of RPL remain unknown which have led to great difficulties and complications in the treatment. MicroRNAs (miRNA) have been shown to be a potential diagnosis tools in different reproductive disorders. This study aimed to investigate the association of four different miRNA variants with the risk of idiopathic RPL (iRPL). A total of 450 women including 225 patients and 225 controls were recruited in this study. DNA was extracted, and genotyped by PCR method. Haplotype analysis, as well as linkage disequilibrium between SNPs, was performed. This study suggested that rs4636297, rs41291957, and rs353292, but not rs531564 can play a risk factor role for iRLP.

Association between ANXA5 haplotypes and the risk of recurrent pregnancy loss

BackgroundAnnexin A5 (ANXA5) haplotypes can increase the risk of recurrent pregnancy loss (RPL). This study aimed to investigate the effect of ANXA5 haplotypes on ANXA5 expression in patients with RPL.MethodsFemale subjects with RPL, parous controls (those who intentionally aborted without medical conditions or complications), and population controls (normal delivery) were studied. Real-time polymerase chain reaction was carried out to evaluate ANXA5 expression in the placenta and peripheral blood. Western blotting and immunohistochemistry were used to assess ANXA5 protein expression. The luciferase assay was performed to detect the effect of M1 and M2 haplotypes on transcription efficiency of the ANXA5 promoter.ResultsWe found that the percentage of the M2 carrier was highest in the RPL group. ANXA5 expression in the placenta and peripheral blood in subjects with RPL was significantly inhibited. Furthermore, ANXA5 expression in subjects carrying the M2 haplotype was remarkably suppressed compared with that in carriers of other haplotypes. Finally, the M2 haplotype decreased the transcription efficiency of the ANXA5 promoter.ConclusionOur findings show that ANXA5 expression is decreased in carriers of the M2 haplotype and that M1/M2 haplotypes in the ANXA5 gene are associated with an increased risk of RPL.

Implications of Decreased Expression of miR-125a with Respect to Its Variant Allele in the Pathogenesis of Recurrent Pregnancy Loss: A Study in a High Incidence Zone.

Pregnancy is controlled by several types of genes and the regulation of their expression is tightly controlled by miRNAs. The present study was carried out to explore the association between miR-125a polymorphic sequence variation and its expression and recurrent pregnancy loss (RPL) compared to full-term healthy controls. A total of 150 women that had experienced two or more RPLs and 180 healthy controls (two or more full-term pregnancies) were recruited, along with 50 product of conception (POC) samples from the corresponding RPL patients, and evaluated for miR-125a SNPs by the polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP), which was confirmed by high resolution melting (HRM)/DNA sequencing. Additionally, the expression of miR-125a was quantified with q–PCR in the maternal plasma of 40 corresponding RPL patients against healthy controls. The frequency of variant genotype CC was significantly higher in RPL cases (19.3%) than controls (10.5%), with an odds ratio of >2 (p = 0.025). The expression levels of miR-125a were markedly decreased in RPL cases compared to healthy controls (p < 0.05). Variant genotype CC was found significantly more often in RPL cases than controls (0.34 vs. 0.20; p < 0.05).In this study, miR-125a rs12976445 C/T revealed that the homozygous CC genotype and C allele were associated with the risk of RPL and significant expression indicates that miR-125a has an important role in RPL etiopathogenesis.