Rs4265085 in GPER1 gene increases the risk for unexplained recurrent spontaneous abortion in Dai and Bai ethnic groups in China

Preimplantation genetic testing as a preventive strategy for the transmission of mitochondrial DNA disorders

Mitochondrial diseases are distinct types of metabolic and/or neurologic abnormalities that occur as a consequence of dysfunction in oxidative phosphorylation, affecting several systems in the body. There is no effective treatment modality for mitochondrial disorders so far, emphasizing the clinical significance of preventing the inheritance of these disorders. Various reproductive options are available to reduce the probability of inheriting mitochondrial disorders, including in vitro fertilization (IVF) using donated oocytes, preimplantation genetic testing (PGT), and prenatal diagnosis (PND), among which PGT not only makes it possible for families to have genetically-owned children but also PGT has the advantage that couples do not have to decide to terminate the pregnancy if a mutation is detected in the fetus. PGT for mitochondrial diseases originating from nuclear DNA includes analyzing the nuclear genome for the presence or absence of corresponding mutations. However, PGT for mitochondrial disorders arising from mutations in mitochondrial DNA (mtDNA) is more intricate, due to the specific characteristics of mtDNA such as multicopy nature, heteroplasmy phenomenon, and exclusive maternal inheritance. Therefore, the present review aims to discuss the utility and challenges of PGT as a preventive approach to inherited mitochondrial diseases caused by mtDNA mutations.

Hyperinsulinemia impairs decidualization via AKT-NR4A1 signaling: new insight into polycystic ovary syndrome (PCOS)-related infertility

BACKGROUND

Investigating the underlying molecular mechanisms responsible for endometrial dysfunction in women with PCOS is essential, particularly focusing on the role of hyperinsulinemia.

METHODS

We explored the role of insulin in the decidualization process using a synthetic decidualization assay. To dissect the effects of PI3K/AKT-NR4A signaling, we employed small interfering RNAs (siRNAs) targeting the NR4A genes and inhibitors of the PI3K/AKT pathway. We also investigated the disruption of AKT-NR4A1 signaling in the endometrium of PCOS female rats induced with dehydroepiandrosterone (DHEA). Quantitative real-time PCR (qRT-PCR) and Western blot (WB) analyses were utilized to evaluate gene expression regulation.

RESULTS

Insulin was found to suppress the expression of decidualization markers in human endometrial stromal cells (hESC) in a dose-dependent manner, concurrently triggering an inappropriate activation of the PI3K/AKT pathway. Members of the NR4A family, as downstream effectors in the PI3K/AKT pathway, were implicated in the insulin-induced disruptions during the decidualization process. Moreover, the endometrium of PCOS models showed significantly elevated levels of phosphorylated (Ser473) AKT, with a corresponding reduction in Nr4a1 protein.

CONCLUSIONS

Our research demonstrates that insulin negatively regulates decidualization in hESC via the PI3K/AKT-NR4A pathway. In vivo analysis revealed a significant dysregulation of the AKT-NR4A1 pathway in the endometrium of PCOS rats. These findings offer novel insights into the pathogenesis of infertility and endometrial disorders associated with hyperinsulinemia in PCOS.

Membrane estrogen receptor and follicle-stimulating hormone receptor

Follicle-stimulating hormone (FSH) and estrogens are fundamental to support reproductive functions. Beside the well-known FSH membrane receptor (FSHR), a G protein-coupled estrogen receptor (GPER) has been found, over the last two decades, in several tissues. It may trigger rapid, non-genomic responses of estradiol, activating proliferative and survival stimuli. The two receptors were co-characterized in the ovary, where they modulate different intracellular signaling cascades, according to the expression level and developmental stage of ovarian follicles. Moreover, they may physically interact to form heteromeric assemblies, suggestive of a new mode of action to regulate FSH-specific signals, and likely determining the follicular fate between atresia and dominance. The knowledge of FSH and estrogen membrane receptors provides a new, deeper level of comprehension of human reproduction.

A missense variant in NCF1 is associated with susceptibility to unexplained recurrent spontaneous abortion

Unexplained recurrent spontaneous abortion (URSA) is a major concern in reproductive medicine. Neutrophil cytosolic factor 1 (NCF1) polymorphisms leading to low production of reactive oxygen species (ROS) are strongly associated with autoimmune diseases. We investigated the association of the missense single nucleotide polymorphism (SNP) rs201802880 (NCF1-339) in NCF1 with URSA and explored its function. We performed NCF1-339 SNP genotyping of samples from 152 Chinese patients with URSA and 72 healthy controls using nested PCR and TaqMan assays. ROS production and RELA (NF-κB subunit) expression in the blood of participants with different NCF1-339 genotypes were determined. The frequencies of the wild-type (GG) and mutant (GA) genotypes remarkably differed between the URSA and control groups. The mutant genotype was associated with an increased risk of recurrent abortion. Furthermore, ROS levels in the URSA group with the GG genotype were significantly higher than those in the group with the GA genotype (p < 0.05). RELA expression in URSA patients with the GA genotype was considerably higher than that in control individuals with the GG genotype. These findings indicate that mutations in NCF1 may increase the risk of URSA via the NADP/ROS/NF-κB signaling pathway, which has implications for the diagnosis and treatment of URSA.

The AGT Haplotype of the ESR2 Gene Containing the Polymorphisms rs2077647A, rs4986938G, and rs1256049T Increases the Susceptibility of Unexplained Recurrent Spontaneous Abortion in Women in the Chinese Hui Population

Background

Estrogen has an important role in unexplained recurrent spontaneous abortion (URSA). Polymorphisms of the ESR1 gene and the ESR2 gene have been identified as risk factors for URSA, but with varied associations in Chinese populations. This study aimed to compare the role of gene polymorphisms of ESR1 and ESR2 and the risk of URSA in the Chinese Hui and Chinese Han populations.

Material/Methods

Chinese Hui women (n=171) and Chinese Han women (n=234) with URSA were compared with healthy controls (n=417) matched by ethnicity and age. Genotyping was performed using direct sequencing and identified three polymorphisms of the ESR1 gene (rs9340799, rs2234693, and rs3798759) and three polymorphisms of the ESR2 gene (rs207764, rs4986938, and rs1256049). The association between ESR1 and ESR2 gene polymorphisms and the risk of URSA was evaluated statistically using the odds ratio (OR) and 95% confidence interval (CI).

Results

No association was detected between the allelic, dominant, and recessive models of ESR1 and ESR2 gene polymorphisms and the risk of URSA in Chinese Han and Hui populations (p>0.05). The distribution of the AGT haplotype containing ESR2 gene polymorphisms rs2077647A, rs4986938G, and rs1256049T was significantly reduced in patients with URSA compared with controls in the Chinese Hui population (OR, 0.29; 95% CI, 0.14–0.62; p=0.0009; p_adj=0.005).

Conclusions

The AGT haplotype of the ESR2 gene containing the polymorphism rs2077647A, rs4986938G, and rs1256049T (ESR2 hap_AGT) was a protective factor for URSA in women in the Chinese Hui population when compared with the Chinese Han population.

Genetic polymorphisms of pharmacogenomic VIP variants in the Dai population from Yunnan province

Background

Pharmacogenomics plays a crucial role in individualized therapy, but the variant information of pharmacogenomics in the Dai population is limited. We therefore aimed to screen very important pharmacogenetic (VIP) in the Dai population and compared differences between Dai and other 25 populations.

Methods

In this study, we genotyped 73 VIP variants from the PharmGKB and compared genotype distribution of variants in Dai with other 25 populations by χ2 test. To assess the genetic relationship among 26 populations, we performed the structure analysis. In addition, pair‐wise F‐statistics (Fst) was calculated to measure the population differentiation.

Results

We found 12, 10, 13, 17, 11, 39, 46, 46, 45, 43, 49, 46, 46, 46, 49, 45, 41, 42, 48, 53, 45, 50, 50, 51, 47, and 50 significantly different variants in Dai compared with other 25 populations. Genetic structure analysis showed Dai had close relationships with CDX (Chinese Dai in Xishuangbanna), CHB (Han Chinese in Beijing), JPT (Japanese in Tokyo), and KHV (Kinh in Ho Chi Minh City, Vietnam). Moreover, Dai is the most similar to KHV according to Fst analysis.

Conclusions

Our study complement the pharmacogenomics information of Dai population from Yunnan province and provide a theoretical basis for personalized medicine.