Genetic Polymorphisms in miR-604A>G, miR-938G>A, miR-1302-3C>T and the Risk of Idiopathic Recurrent Pregnancy Loss

MIR938 rs2505901 T>C polymorphism is associated with increased neuroblastoma risk in Chinese children

Neuroblastoma (NB) is a kind of childhood cancer that is a prevailing and deadly solid neoplasm among pediatric malignancies. The transcriptional output of MIR938 is capable of participating in the posttranscriptional modulation of gene expression, whereby it exerts its regulatory effect by modulating both the stability and translation of target mRNAs. Previous studies showed that MIR938 was associated with many cancers. Hence, functional genetic variants in the MIR938 can be attributed to NB risk. We recruited 402 neuroblastoma patients and 473 controls from the Children's Hospital of Nanjing Medical University and genotyped one MIR938 single-nucleotide polymorphism (SNP) (rs2505901 T>C). There were significant associations between the rs2505901 T>C and NB risk [CC vs. TT: adjusted odds ratio (OR) = 1.90, 95% confidence interval (CI) = 1.02-3.55, P=0.045; CC vs. TT/TC: adjusted OR = 2.02, 95% CI = 1.09-3.75, P=0.026]. This analysis of genotypes revealed that T>C increased the risk of NB. Some borderline significant different relationships were observed in the stratified analyses: age ≤ 18 months (adjusted OR = 2.95, 95% CI = 0.92-9.51, P=0.070), male sex (adjusted OR = 2.19, 95% CI = 0.95-5.08, P=0.067), and clinical stage III+IV (adjusted OR = 2.12, 95% CI = 0.98-4.56, P=0.055). The present study revealed that the MIR938 rs2505901 T>C polymorphism may be a potential risk factor for neuroblastoma in Chinese children. In the long term, conducting large and diverse sample studies from different ethnicities will indeed be crucial in determining the role of MIR938 polymorphisms in NB risk. By including individuals from various ethnic backgrounds, researchers can account for potential genetic variations that may exist between populations.

miR604A>G gene polymorphism is associated with recurrent pregnancy loss in Turkish women

OBJECTIVE

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. In this study, we aimed to examine the association between miR604 (rs2368393) A>G gene polymorphism and the risk of recurrent miscarriage in the Turkish population.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

First-Trimester Screening for Miscarriage or Stillbirth-Prediction Model Based on MicroRNA Biomarkers

We evaluated the potential of cardiovascular-disease-associated microRNAs to predict in the early stages of gestation (from 10 to 13 gestational weeks) the occurrence of a miscarriage or stillbirth. The gene expressions of 29 microRNAs were studied retrospectively in peripheral venous blood samples derived from singleton Caucasian pregnancies diagnosed with miscarriage (n = 77 cases; early onset, n = 43 cases; late onset, n = 34 cases) or stillbirth (n = 24 cases; early onset, n = 13 cases; late onset, n = 8 cases; term onset, n = 3 cases) and 80 selected gestational-age-matched controls (normal term pregnancies) using real-time RT-PCR. Altered expressions of nine microRNAs (upregulation of miR-1-3p, miR-16-5p, miR-17-5p, miR-26a-5p, miR-146a-5p, and miR-181a-5p and downregulation of miR-130b-3p, miR-342-3p, and miR-574-3p) were observed in pregnancies with the occurrence of a miscarriage or stillbirth. The screening based on the combination of these nine microRNA biomarkers revealed 99.01% cases at a 10.0% false positive rate (FPR). The predictive model for miscarriage only was based on the altered gene expressions of eight microRNA biomarkers (upregulation of miR-1-3p, miR-16-5p, miR-17-5p, miR-26a-5p, miR-146a-5p, and miR-181a-5p and downregulation of miR-130b-3p and miR-195-5p). It was able to identify 80.52% cases at a 10.0% FPR. Highly efficient early identification of later occurrences of stillbirth was achieved via the combination of eleven microRNA biomarkers (upregulation of miR-1-3p, miR-16-5p, miR-17-5p, miR-20a-5p, miR-146a-5p, and miR-181a-5p and downregulation of miR-130b-3p, miR-145-5p, miR-210-3p, miR-342-3p, and miR-574-3p) or, alternatively, by the combination of just two upregulated microRNA biomarkers (miR-1-3p and miR-181a-5p). The predictive power achieved 95.83% cases at a 10.0% FPR and, alternatively, 91.67% cases at a 10.0% FPR. The models based on the combination of selected cardiovascular-disease-associated microRNAs had very high predictive potential for miscarriages or stillbirths and may be implemented in routine first-trimester screening programs.

Two single nucleotide variants in the miR-23a promoter affect granulosa cell apoptosis

microRNAs (miRNAs) are well known to be important in mammalian female fertility. However, the genetic regulation of miRNAs associated with female fertility remains largely unknown. Here, we report that two single-nucleotide variants (SNVs) in the miR-23a promoter strongly influence miR-23a transcription and function in granulosa cell (GC) apoptosis. Two novel SNVs, g.-283G>C and g.-271C>T, were detected in the porcine miR-23a promoter by pooled-DNA sequencing. Furthermore, SNVs in the promoter region influenced miR-23a transcription in porcine GCs by altering its promoter activity. Functionally, SNVs in the promoter strongly influenced miR-23a regulation of early apoptosis in porcine GCs cultured in vitro. In addition, a preliminary association analysis showed that the combined genotypes of the two SNVs, rather than a single SNV, were tentatively associated with sow fertility traits in a Large White population. Overall, our findings suggest that the SNVs g.-283G>C and g.-271C>T in the miR-23a promoter are causal variants affecting GC apoptosis and miR-23a may be a potential small-molecule nonhormonal drug for regulating female fertility.

miR-146a, miR-196a2, miR-499, and miR-149 linked with susceptibility to acute lymphoblastic leukemia: A case-control study in Tunisia

BACKGROUND

MicroRNAs (miRNAs) are promising biomarkers of hematological malignancies, including acute lymphoblastic leukaemia (ALL). Recent studies revealed that miRNA single nucleotide polymorphisms (miR-SNP) modulate cancer risk by regulating various signaling pathways. However, their association with altered risk of ALL yielded inconsistent results.

OBJECTIVE

This study aims to investigate the association of four miR-SNPs with altered risk of ALL risk in Tunisian, the first on North African population.

METHODS

A retrospective case-control study exploring the association of miR-146a, miR-196a2, miR-499, and miR-149 SNPs in 126 ALL patients and 126 healthy controls.

RESULTS

Of the tested variants, significantly lower minor allele frequencies (MAF) of miR-146a C-allele and higher MAF frequency of miR-149 T-allele (P = 0.006) were seen in ALL cases. The association of miR-149 rs2292832 (Pc = 0.02), but not miR-146a rs2910164 (Pc = 0.11) persisted after correcting for multiple comparisons. Significantly reduced prevalence of miR-146a G/C genotype and higher frequency of miR-149 C/T genotype were seen in ALL cases vs. control subjects, which translated into negative association of miR-146a (rs2910164) with ALL according to the codominant and dominant models. Similarly, miR-149 (rs2292832) was positively associated with ALL according to the codominant and dominant genetic models. Three combinations comprising miR-146a/miR-196a2 GG vs CT + TT genotype combination, miR-146a/miR-499 GG vs TC + CC genotype combination, and miR-146a/miR-149 GG vs CT + TT genotype combination, were less frequent in ALL patients than in controls, and were negatively associated with the presence of ALL.

CONCLUSION

Our study suggests that miR-146a and miR-149 polymorphisms constitute biomarkers for personalized diagnosis of ALL.

A Mutation in Endogenous saRNA miR-23a Influences Granulosa Cells Response to Oxidative Stress

Phenotypes are the result of the interaction between the gene and the environment, so the response of individuals with different genotypes to an environment is variable. Here, we reported that a mutation in miR-23a influences granulosa cells (GCs) response to oxidative stress, a common mechanism of environmental factors affecting female reproduction. We showed that nuclear miR-23a is a pro-apoptotic miRNA in porcine GCs through the activation of the transcription and function of NORHA, a long non-coding RNA (lncRNA) induces GC apoptosis and responses to oxidative stress. Mechanistically, miR-23a acts as an endogenous small activating RNA (saRNA) to alter histone modifications of the NORHA promoter through the direct binding to its core promoter. A C > T mutation was identified at −398 nt of the miR-23a core promoter, which created a novel binding site for the transcription factor SMAD4 and recruited the transcription repressor SMAD4 to inhibit miR-23a transcription and function in GCs. Notably, g.−398C > T mutation in the miR-23a promoter reduced GCs response to oxidative stress. In addition, g.−398C > T mutation was significantly associated with sow fertility traits. In short, our findings preliminarily revealed the genetic basis of individual differences in the response to oxidative stress from the perspective of a single mutation and identified miR-23a as a candidate gene for the environmental adaptation to oxidative stress.

Mouse Cre drivers: tools for studying disorders of the human female neuroendocrine-reproductive axis†

Benign disorders of the human female reproductive system, such primary ovarian insufficiency and polycystic ovary syndrome are associated with infertility and recurrent miscarriage, as well as increased risk of adverse health outcomes, including cardiovascular disease and type 2 diabetes. For many of these conditions, the contributing molecular and cellular processes are poorly understood. The overarching similarities between mice and humans have rendered mouse models irreplaceable in understanding normal physiology and elucidating pathological processes that underlie disorders of the female reproductive system. The utilization of Cre-LoxP recombination technology, which allows for spatial and temporal control of gene expression, has identified the role of numerous genes in development of the female reproductive system and in processes, such as ovulation and endometrial decidualization, that are required for the establishment and maintenance of pregnancy in mammals. In this comprehensive review, we provide a detailed overview of Cre drivers with activity in the neuroendocrine-reproductive axis that have been used to study disruptions in key intracellular signaling pathways. We first summarize normal development of the hypothalamus, pituitary, ovary, and uterus, highlighting similarities and differences between mice and humans. We then describe human conditions resulting from abnormal development and/or function of the organ. Finally, we describe loss-of-function models for each Cre driver that elegantly recapitulate some key features of the human condition and are associated with impaired fertility. The examples we provide illustrate use of each Cre driver as a tool for elucidating genetic and molecular underpinnings of reproductive dysfunction.

Role of miRNA polymorphism in recurrent pregnancy loss: a systematic review and meta-analysis

There are a plethora of publications on the role of miRNA gene polymorphism and its association with recurrent pregnancy loss (RPL), but a lack of uniformity in the studies available due to the variable subject population, heterogeneity and contrary results of significance. Rigorous data mining was done through PubMed, SCOPUS, Cochrane library, Elsevier and Google Scholar to extract the studies of interest published until June 2021. A total of eight SNPs of miRNAs have been included, where ≥2 studies per SNPs were available. Analysis was done on the basis of pooled odds ratios and 95% CI. This is the first meta-analysis on miRNA SNPs in RPL that suggests that rs11614913, rs3746444 and rs2292832 biomarkers may decrease the risk of RPL under different genetic models.