Analysis of the PvuII and XbaI polymorphisms in the estrogen receptor alpha gene in girls with central precocious puberty: a pilot study

A comprehensive meta-analysis to identify susceptibility genetic variants for precocious puberty

PURPOSE

Currently, several genetic variants in ERα gene (rs2234693 and rs9340799), ERβ gene (rs1256049 and rs4986938), KISS1 gene (rs4889, rs1132506 and rs5780218), LIN28B gene (rs314263, rs314276 and rs314280), and MKRN3 gene (rs2239669) have been repeatedly explored for their contribution to precocious puberty (PP) susceptibility. However, the results remain conflicting rather than conclusive. We here performed a meta-analysis to identify the real susceptibility genetic variants for PP.

METHODS

After screening by inclusion criteria, 20 related studies were finally included in this meta-analysis. The odds ratios and 95% confidence intervals were calculated to assess the strength of association. Sensitive analysis, publication bias, and trial sequential analysis (TSA) were performed to evaluate the stability and reliability of results.

RESULTS

Rs2234693, rs9340799, and rs1256049 were significantly associated with PP susceptibility (p < 0.0084). Stratified analysis according to ethnicity showed that rs2234693 and rs9340799 were significantly associated with PP susceptibility in Asian and Chinese populations. Stratified analysis according to PP subtype showed that rs2234693 and rs9340799 were significantly associated with idiopathic central PP susceptibility in Asian and Chinese populations (p < 0.0084). The results of publication bias, sensitivity analysis, and TSA provided solid evidence for the association between these three variants and PP susceptibility.

CONCLUSIONS

Rs2234693 and rs9340799 in ERα gene and rs1256049 in ERβ gene may serve as susceptive factors for PP development. The present finding should be confirmed in replication studies and reinforced in functional studies, which will ultimately improve the feasibility of the application of these three PP-susceptible loci in clinical practice.

The Role of SNPs in the Pathogenesis of Idiopathic Central Precocious Puberty in Girls

The initiation of puberty is a crucial timepoint of development, with its disruptions being associated with multiple physical and psychological complications. Idiopathic Central Precocious Puberty (iCPP) has been correlated with Single-Nucleotide Polymorphisms (SNPs) of certain genes that are implicated in various steps of the process of pubertal onset. The aim of this review was to gather current knowledge on SNPs of genes associated with iCPP. We searched articles published on the PubMed, EMBASE and Google Scholar platforms and gathered current literature. KISS1, KISS1R, PLCB1, PRKCA, ITPR1, MKRN3, HPG axis genes, NPVF/NPFFR1, DLK1, KCNK9Q, LIN28B, PROK2R, IGF-1, IGF2, IGF-1R, IGF-2R, IGFBP-3, insulin, IRS-1, LEP/LEPR, PPARγ2, TAC3, TACR3, Estrogen receptors, CYP3A4 and CYP19A1 were studied for implication in the development of precocious puberty. SNPs discovered in genes KISS1, KISS1R, PLCB1, MKRN3, NPVF, LIN28B, PROK2R, IRS-1 TAC3, and CYP3A4 were significantly correlated with CPP, triggering or protecting from CPP. Haplotype (TTTA)13 in CYP19A1 was a significant contributor to CPP. Further investigation of the mechanisms implicated in the pathogenesis of CPP is required to broaden the understanding of these genes’ roles in CPP and possibly initiate targeted therapies.

Study of Xbal and Pvull polymorphisms of estrogen receptor alpha (ERα) gene in girls with precocious/early puberty

PURPOSE

Studies examining association of estrogen receptor alpha (ERα) polymorphisms with early puberty are scarce and results are controversial; data in Caucasian girls are lacking. Main objective was to determine association of Xbal and Pvull polymorphisms of ERα gene in Greek girls with precocious/early puberty METHODS: We studied 107 girls with idiopathic precocious/early puberty and 81 young women with pubertal maturation within normal age (controls). Pubertal stage, height SDS (HSDS), and BMI z-score were determined in patients. In controls, height was measured and menarcheal age was self-reported. All participants in the study were genotyped for XbaI and PvuII polymorphisms of the ERα gene.

RESULTS

There was no significant difference in XbaI and PvuII polymorphisms between patients and controls. Homozygous, xx and pp, girls had an earlier onset of puberty, although non-significant, than heterozygous or with no polymorphisms p = 0.9; in girls with pubertal onset <7 years, the association tended to become significant, p = 0.09. Girls with xxpp genotype were significantly taller, HSDS 1.63, p = 0.014. In controls, homozygosity for Xbal (xx) and PvuII (pp) was associated with significantly earlier menarche than in women with no polymorphism, p = 0.013 and p = 0.026, respectively, and xxpp genotype was associated with taller adult height, p = 0.017.

CONCLUSION

XbaI and PvuII polymorphisms are not related to idiopathic precocious/early puberty. Early pubertal girls homozygous for both polymorphisms presented earlier onset of puberty, although statistically non-significant, and taller height than girls heterozygous or without these polymorphisms. Homozygosity for both polymorphisms is associated with earlier menarche and taller adult height.

MiR-664-2 impacts pubertal development in a precocious-puberty rat model through targeting the NMDA receptor-1†

Precocious puberty (PP) commonly results from premature activation of the hypothalamic-pituitary-gonadal axis (HPGA). Gonadotropin-releasing hormone (GnRH) is the initial trigger for HPGA activation and plays an important role in puberty onset. N-methyl-D-aspartate (NMDA) can promote pulsatile GnRH secretion and accelerates puberty onset. However, the mechanism of N-methyl-D-aspartate receptors (NMDARs) in PP pathogenesis remains obscure. We found that serum GnRH, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estrogen (E2) levels, hypothalamic NMDAR1, and GnRH mRNA expression peaked at the vaginal opening (VO) day. Next, the hypothalamic NMDAR1 mRNA and protein levels in rats treated with danazol, a chemical commonly effecting on the reproductive system, were significantly increased at the VO day (postnatal day 24) compared to controls, accompanied by enhanced serum GnRH, LH, FSH, and E2 levels. Further, microRNA-664-2 (miR-664-2) was selected after bioinformatics analysis and approved in primary hypothalamic neurons, which binds to the 3'-untranslated regions of NMDAR1. Consistently, the miR-664-2 expression in hypothalamus of the Danazol group was decreased compared to Vehicle. Our results suggested that attenuated miR-664-2 might participate in PP pathogenesis through enhancing the NMDAR1 signaling.