BackgroundPolycystic ovary syndrome (PCOS), the commonest endocrine disorder affecting young women, appears to be a multigenic trait with contributing genes being unclear. Hence, analysis of polymorphisms in multiple candidate genes is required. Currently available genotyping methods are expensive, time-consuming with limited analytical sensitivity.Aim(i) Develop and validate high resolution melting (HRM) assay and allele-specific real-time quantitative PCR (AS-qPCR) for genotyping selected SNPs associated with PCOS.(ii) Identify selected SNPs and their association with a Sri Lankan cohort of well-characterized PCOS.MethodsDNA was extracted from women with well-characterized PCOS from adolescence (n = 55) and ethnically matched controls (n = 110). FTO (Fat mass and obesity associated gene; rs9939609), FSHB (Follicle stimulating hormone beta subunit; rs6169), FSHR (Follicle stimulating hormone receptor; rs6165/rs6166), and INSR (Insulin receptor; rs1799817) genes were genotyped using HRM assay. GnRH1 (Gonadotropin releasing hormone; rs6185), LHB (Luteinizing hormone beta subunit; rs1800447/rs34349826) and LHCGR (Luteinizing hormone/choriogonadotropin receptor; rs2293275) genes were genotyped using AS-qPCR method. Genotyping results were validated using Sanger sequencing.ResultsA significant association was observed within FTO gene polymorphism (rs9939609) and PCOS. Genotype frequency of FTO gene (rs9939609)—cases versus controls were TT-36.4% vs.65.4% (p<0.05), AT-23.6% vs.20.9%, AA-40% vs.13.6% (p<0.05). Genotype frequencies of the SNPs GnRH1 (rs6185), FSHB (rs6169), FSHR (rs6165 & rs6166), LHB (rs1800447 & rs34349826), LHCGR (rs2293275) and INSR (rs1799817) were not significantly different between cases and controls (p>0.05). Only the mutant alleles were observed for LHB rs1800447 and rs34349826 SNPs in both groups. The HRM and AS-qPCR assay results had 100% concordance with sequencing results.ConclusionsFTO gene rs9939609 polymorphism is significantly more prevalent among Sri Lankan PCOS subjects while the other selected SNPs of HPG axis genes and INSR gene showed no association. HRM and AS-qPCR assays provide a reliable, fast and user-friendly genotyping method facilitating wider implication in clinical practice.

Polycystic ovary syndrome (PCOS) is the commonest endocrine disorder affecting women of reproductive age. Its aetiology, though yet unclear, is presumed to have an oligogenic basis interacting with environmental factors. Kisspeptins are peptide products of Kiss1 gene that control the hypothalamic pituitary (HPG) axis by acting via G protein-coupled receptor known as GPR54. There is paucity of data on the role of Kiss1 and GPR54 gene in PCOS. We aimed to identify the polymorphisms in Kiss1 and GPR54 genes and explore their association with serum kisspeptin levels among Sri Lankan women with well-characterized PCOS. Consecutive women with PCOS manifesting from adolescence (n=55) and adult controls (n=110) were recruited. Serum kisspeptin and testosterone levels were determined by ELISA method. Whole gene sequencing was performed to identify the polymorphisms in Kiss1 and GPR54 genes. Serum kisspeptin and testosterone concentrations were significantly higher in women with PCOS than controls: kisspeptin 4.873nmol/L versus 4.127nmol/L; testosterone 4.713nmol/L versus 3.415 nmol/L, p<0.05. Sequencing the GPR54 gene revealed 5 single nucleotide polymorphisms (SNPs), rs10407968, rs1250729403, rs350131, chr19:918686, and chr19:918735, with two novel SNPs (chr19:918686 and chr19:918735), while sequencing the Kiss1 gene revealed 2 SNPs, rs5780218 and rs4889. All identified SNPs showed no significant difference in frequency between patients and controls. GPR54 gene rs350131 polymorphism (G/T) was detected more frequently in our study population. The heterozygous allele (AG) of GPR54 gene novel polymorphism chr19:918686 showed a marginal association with serum kisspeptin levels (p=0.053). Genetic variations in GPR54 and Kiss1 genes are unlikely to be associated with PCOS among Sri Lankan women manifesting from adolescence. Meanwhile the heterozygous allele of chr19:918686 is probably associated with serum kisspeptin concentrations, which suggests a potential role in the aetiology of PCOS.

Background: PCOS is a common disorder of women due to genetic, endocrine and environmental effects that manifests from puberty. The rs9939609 variant of fat mass and obesity associated (FTO) gene is linked to metabolic derangement in PCOS. We previously identified FTO (rs9939609) as a susceptibility locus for PCOS among Sri Lankan women and also explored the role of kisspeptin. Associated factors of the FTO candidate gene among South Asians with PCOS are unknown. Methods: This study aimed to determine the association between FTO (rs9939609) polymorphism with clinical (BMI, acanthosis nigricans, hirsutism) and biochemical (serum kisspeptin and testosterone levels) characteristics of PCOS in a cohort of Sri Lankan women. Genetic and clinical data including serum kisspeptin and testosterone concentrations of our previously reported cases (n=55) and controls (n=110) were re-analyzed, specifically for an association with rs9939609 variant of FTO gene. Results: Logistic regression analysis (AA – OR=5.7, 95% CI=2.41-13.63, p<0.05) and genetic inheritance analysis (AA – OR=5.49, 95%CI=2.34-12.88, p<0.05) showed that FTO (rs9939609) polymorphism is significantly associated with PCOS and its metabolic manifestations. Serum testosterone was significantly higher in affected women with mutant genotypes (AA+AT) than the normal allele (TT) (p<0.05). Although serum kisspeptin was higher in subjects with PCOS and mutant alleles than controls, this difference was not significant (p>0.05). Conclusion: FTO gene variant rs9939609 is associated with hyperandrogenemia and metabolic manifestations of PCOS among women of Sri Lankan descent with the well-characterized phenotype. Serum kisspeptin and the FTO genotypes lack a significant association when adjusted for confounders.

Polycystic Ovary Syndrome (PCOS) is a common endocrine disorder, present in 5-13% women of reproductive age. The endocrine manifestations of PCOS include excess androgen production of ovarian and/or adrenal origin and arrested follicular development leading to chronic oligo-or anovulation. Long term health risks of women with PCOS include cardiovascular disease, type 2 diabetes mellitus and endometrial cancer. PCOS is diagnosed by chronic anovulation, polycystic ovaries on ultrasound and biochemical/clinical manifestations of hyperandrogenism. Phenotype expression is heterogeneous and varies throughout the woman's life cycle, making early confirmation difficult. South Asians with anovulatory PCOS manifest severe symptoms at a younger age, with greater insulin resistance and a higher prevalence of the metabolic syndrome than white Europeans, thereby reflecting their ethnic propensity to type 2 diabetes mellitus. PCOS appears to be a multigenic trait, although contributing genes remain undefined yet. Several studies have been carried out to identify the candidate genes and polymorphisms affecting the multiple biological pathways of PCOS. The main objective of this article is to review the role of genes regulating the Hypothalamus-Pituitary-Gonadal (HPG) axis -mainly KISS1, GPR54 receptor gene, GnRH (Gonotropin Releasing Hormone), GnRHR (Gonotropin Releasing Hormone Receptor), FSH (Follicle Stimulating Hormone), FSHR (Follicle Stimulating Hormone Receptor), LHβ (Luteinizing Hormone beta subunit) and LHCGR (Luteinizing Hormone/Choriogonadotropin receptor) genes; with special focus on its association with PCOS.

Background: PCOS is a common disorder of women due to genetic, endocrine and environmental effects that manifests from puberty. The rs9939609 variant of fat mass and obesity associated (FTO) gene is linked to metabolic derangement in PCOS. We previously identified FTO (rs9939609) as a susceptibility locus for PCOS among Sri Lankan women and also explored the role of kisspeptin. Associated factors of the FTO candidate gene among South Asians with PCOS are unknown.Methods: This study aimed to determine the association between FTO (rs9939609) polymorphism with clinical (BMI, acanthosis nigricans, hirsutism) and biochemical (serum kisspeptin and testosterone levels) characteristics of PCOS in a cohort of Sri Lankan women. Genetic and clinical data including serum kisspeptin and testosterone concentrations of our previously reported cases (n = 55) and controls (n = 110) were re-analyzed, specifically for an association with rs9939609 variant of FTO gene. Results: Logistic regression analysis (AA -OR = 5.7, 95% CI = 2.41-13.63, p < 0.05) and genetic inheritance analysis (AA -OR = 5.49, 95%CI = 2.34-12.88, p < 0.05) showed that FTO (rs9939609) polymorphism is significantly associated with PCOS and its metabolic manifestations. Serum testosterone was significantly higher in affected women with mutant genotypes (AA+AT) than with the normal allele (TT) (p < 0.05). Although serum kisspeptin was higher in subjects with PCOS and mutant alleles than controls, this difference was not significant (p > 0.05).Conclusion: FTO gene variant rs9939609 is associated with hyperandrogenemia and metabolic manifestations of PCOS among women of Sri Lankan descent with the well-characterized phenotype. Serum kisspeptin and the FTO genotypes lack a significant association when adjusted for confounders.