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 About 30% of patients treated with second generation antipsychotics (SGA) experience weight gain. Although there is evidence that the FTO gene is associated with obesity its role in antipsychotic induced weight gain is not so clear. Methods A genetic association study was carried out to identify the association between FTO rs9939609 and antipsychotic induced weight gain. Sample consisted of 180 cases and 120 controls. Cases were patients diagnosed with schizophrenia or schizoaffective disorder, treated with second-generation antipsychotics for a minimum of 3 months, and had gained at least 10% of body weight. Controls were patients with schizophrenia treated with second-generation antipsychotics for a minimum of 3 months but had not gained ≥10% of body weight. Genomic DNA was extracted from whole blood. Polymerase chain reaction of the samples was done. Real-time quantitative PCR (qPCR) was carried out using BIO-RAD CFX96 Touch TM PCR detection system. Results Females were significantly more among cases (58.3%) than controls (35%). Cases (52.4%) were significantly more likely to be overweight or obese than controls (13.8%). Genotype distribution was in Hardy-Weinberg equilibrium (p=0.43). Cochran-Armitage trend test was not significant. Risk of antipsychotic induced weight gain in the AA genotype [OR 1.69 (95% CI 0.74-3.86)] and AT genotype [OR 1.1 (95% CI 0.67-1.79)] were not significantly higher than the TT genotype. Recessive model showed that AA/AT genotypes were at significantly higher risk of being obese/overweight [OR 1.84 (95% CI 1.05-3.2)]. Conclusions There was no significant association between FTO rs9939609 and antipsychotic induced weight gain. AA/AT genotypes had significantly higher risk of overweight/obesity.

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