Body mass index stratified meta-analysis of genome-wide association studies of polycystic ovary syndrome in women of European ancestry

The Role of Gene Alterations in the Pathogenesis of Polycystic Ovary Syndrome

Family studies have shown that polycystic ovary syndrome (PCOS) has probable genetic transmission because of a high incidence of relatives who present clinical or biochemical characters of the syndrome. However, initial candidate gene studies were unsuccessful. Genome wide association studies (GWASs) have shown that at least 29 gene alterations are common in PCOS, but it has been calculated that the altered genes found by GWASs may represent only 10% of affected patients. Rare altered uncoding genes may explain the syndrome in an additional group of patients. In many other patients, the altered genes found by GWASs may represent a risk condition for the development of the syndrome, and new candidate gene studies have shown that some gene alterations that mainly concern androgen production may be common in PCOS. Finally, in most patients, epigenetic and environmental factors may be necessary to transform a risk condition into this common and important syndrome.

Interface between reproductive and metabolic dysfunction in polycystic ovary syndrome

PURPOSE OF REVIEW

New concepts have emerged regarding how interrelationships of hyperandrogenism and hyperinsulinemia from systemic insulin resistance contribute to the origins of polycystic ovary syndrome (PCOS). Although these androgen-insulin interrelationships are associated with several reproductive and metabolic variables, their specific cause and effect relationships remain unclear. This review examines specific causal relationships between hyperandrogenism and hyperinsulinemia from systemic insulin resistance to understand how these complex interactions contribute to the phenotypic expression of PCOS.

RECENT FINDINGS

Clinical interventions for the treatments of hyperandrogenism and hyperinsulinemia from systemic insulin resistance as well as in-vitro studies of androgen and insulin actions on critical target tissues are examined to understand why androgen-insulin interrelationships are central to the origins of PCOS.

SUMMARY

Bidirectional interrelationships between hyperandrogenism and hyperinsulinemia from systemic insulin resistance in normal-weight PCOS women may have originally evolved as an ancient metabolic adaptation to simultaneously favor fat storage and energy utilization for survival and reproduction during famine. These androgen-insulin interactions in PCOS now predispose to metabolic diseases and pregnancy complications in today's obesogenic environment and, therefore, require improved preventive healthcare to optimize the long-term health of PCOS women and their children.

A genome-wide association study of anti-Müllerian hormone (AMH) levels in Samoan women

Study question

Can a genome-wide association study (GWAS) and transcriptome-wide association study (TWAS) help identify genetic variation or genes associated with circulating anti-Müllerian hormone (AMH) levels in Samoan women?

Summary answer

We identified eleven genome-wide suggestive loci (strongest association signal in ARID3A 19-946163-G-C [ p = 2.32 × 10⁻⁷]) and seven transcriptome-wide significant genes ( GINS2, SENP3, USP7, TUSC3, MAFA, METTL4, NDFIP1 [all with a p < 2.50 × 10⁻⁶]) associated with circulating AMH levels in Samoan women.

What is known already

Three prior GWASs of AMH levels identified eight loci in premenopausal women of European ancestry (AMH, MCM8, TEX41 , CHECK2, CDCA7 , EIF4EBP1, BMP4 and an uncharacterized non-coding RNA gene CTB-99A3.1 ), among which the MCM8 locus was shared among all three studies.

Study design size duration

We included a sample of 1,185 women from two independently recruited samples: a family study ( n = 212; [age: 18 to 40 years]) recruited in 2002-03 from Samoa and American Samoa; and the Soifua Manuia Study ( n = 973; age: 25 to 51 years), a crosssectional population-based study recruited in 2010 from Samoa.

Participants/materials setting methods

Serum AMH levels were measured using enzyme linked immunosorbent assays (ELISA). We performed GWASs in the two participant samples using a Cox mixed-effects model to account for AMH levels below detectable limits and adjusted for centered age, centered age², polity, and kinship via kinship matrix. The summary statistics were then meta-analyzed using a fixed-effect model. We annotated the variants with p < 1 × 10⁻⁵ and calculated posterior probability of causality for prioritization. We further annotated variants using FUMA and performed colocalization and transcriptome-wide association analysis. We also assessed whether any previously reported loci were replicated in our GWAS.

Main results and the role of chance

We identified eleven novel genome-wide suggestive loci ( p < 1 × 10⁻⁵) associated with AMH levels and replicated EIF4EBP1, a previously reported AMH locus, in the GWAS. The lead variant in ARID3A , 19-946163-G-C is in high linkage disequilibrium ( r ² = 0.79) with the known age-at-menopause variant 19-950694-G-A. Nearby KISS1R is a biologically plausibility causal gene in the region; kisspeptin regulates ovarian follicle development and has been linked to AMH levels. Further investigation of the ARID3A locus is warranted.

Limitations reasons for caution

The main limitations of our study are the small sample size for a GWAS and the use of the transcription model trained on mostly European samples from the Genotype Tissue Expression (GTEx) project, which may have led to reduced power to detect genotype-expression associations. Our findings need to be validated in larger Polynesian cohorts.

Wider implications of the findings

In addition to replicating one of the eight previously discovered AMH loci, we identified new suggestive associations. It is known that the inclusion of founder populations aids in the discovery of novel loci. These findings could enhance our understanding of AMH and AMH-related reproductive phenotypes (ovarian reserve, age at menopause, premature ovarian failure, and polycystic ovary syndrome) and help build a screening approach for women at risk for these phenotypes using genetically predicted AMH levels.

Study funding/competing interests

This work was funded by NIH grants R01-HL093093 (PI: S.T.M.), R01-HL133040 (PI: R.L.M.), and T90-DE030853 (PI: C.S. Sfeir). Molecular data for the Trans-Omics in Precision Medicine (TOPMed) Program was supported by the National Heart, Lung and Blood Institute (NHLBI). The content is solely the responsibility of the authors and does not represent the official views of the National Institutes of Health.

Metabolic Dysfunction-Associated Steatotic Liver Disease and Polycystic Ovary Syndrome: A Complex Interplay

Metabolic dysfunction-associated steatotic liver disease (MASLD) and polycystic ovary syndrome (PCOS) are prevalent conditions that have been correlated with infertility through overlapped pathophysiological mechanisms. MASLD is associated with metabolic syndrome and is considered among the major causes of chronic liver disease, while PCOS, which is characterized by ovulatory dysfunction and hyperandrogenism, is one of the leading causes of female infertility. The pathophysiological links between PCOS and MASLD have not yet been fully elucidated, with insulin resistance, hyperandrogenemia, obesity, and dyslipidemia being among the key pathways that contribute to liver lipid accumulation, inflammation, and fibrosis, aggravating liver dysfunction. On the other hand, MASLD exacerbates insulin resistance and metabolic dysregulation in women with PCOS, creating a vicious cycle of disease progression. Understanding the intricate relationship between MASLD and PCOS is crucial to improving clinical management, while collaborative efforts between different medical specialties are essential to optimize fertility and liver health outcomes in individuals with MASLD and PCOS. In this review, we summarize the complex interplay between MASLD and PCOS, highlighting the importance of increasing clinical attention to the prevention, diagnosis, and treatment of both entities.

Polycystic ovary syndrome

Despite affecting ~11-13% of women globally, polycystic ovary syndrome (PCOS) is a substantially understudied condition. PCOS, possibly extending to men's health, imposes a considerable health and economic burden worldwide. Diagnosis in adults follows the International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome, requiring two out of three criteria - clinical or biochemical hyperandrogenism, ovulatory dysfunction, and/or specific ovarian morphological characteristics or elevated anti-Müllerian hormone. However, diagnosing adolescents omits ovarian morphology and anti-Müllerian hormone considerations. PCOS, marked by insulin resistance and hyperandrogenism, strongly contributes to early-onset type 2 diabetes, with increased odds for cardiovascular diseases. Reproduction-related implications include irregular menstrual cycles, anovulatory infertility, heightened risks of pregnancy complications and endometrial cancer. Beyond physiological manifestations, PCOS is associated with anxiety, depression, eating disorders, psychosexual dysfunction and negative body image, collectively contributing to diminished health-related quality of life in patients. Despite its high prevalence persisting into menopause, diagnosing PCOS often involves extended timelines and multiple health-care visits. Treatment remains ad hoc owing to limited understanding of underlying mechanisms, highlighting the need for research delineating the aetiology and pathophysiology of the syndrome. Identifying factors contributing to PCOS will pave the way for personalized medicine approaches. Additionally, exploring novel biomarkers, refining diagnostic criteria and advancing treatment modalities will be crucial in enhancing the precision and efficacy of interventions that will positively impact the lives of patients.