FTO gene variants are not associated with polycystic ovary syndrome in women from Southern Brazil

- Polycystic ovary syndrome is an endocrine disorder presenting polygenic traits.
- PCOS is frequently associated with obesity and insulin resistance.
- FTO gene variants and endocrine variables were studied in Brazilian women with PCOS.
- FTO genotypes and haplotypes were not related to PCOS in women from Southern Brazil.
- Risk alleles of SNPs in FTO were associated with higher fasting glucose levels.

Background and aimsPolycystic ovary syndrome (PCOS) is a common endocrine disorder, presenting polygenic traits as well as determined by environmental factors. Given the overlap between PCOS and obesity, we assessed the frequencies of SNPs rs9939609 and rs8050136 in intron 1 of the FTO gene and their haplotypes in women with PCOS and healthy controls with regular cycles from Southern Brazil and investigated their relationship with metabolic traits and endocrine parameters.Subjects and methodsThe sample comprised 298 women (199 with PCOS and 99 non-hirsute women with regular ovulatory cycles). FTO genotyping was done by real-time PCR. Haplotypes were constructed from the combination of both polymorphisms. Frequencies were inferred using PHASE 2.1.1 software.ResultsThe distribution of rs9939609 (PCOS: 32.6% TT, 45.9% TA, 21.5% AA; controls: 33.3% TT, 49.0% TA, 17.7% AA) and rs8050136 (PCOS: 21.7% AA, 43.3% AC, 35.0% CC; controls: 14.9% AA, 48.9% AC, 36.2% CC) was similar between groups. The mean age of participants was 22.7 ± 7.1 years. Women with PCOS had significantly higher BMI, waist circumference, total testosterone, and FAI vs. controls. In the PCOS group, no differences between genotypes and haplotypes were found for clinical variables. The presence of at least one risk allele for polymorphisms rs9939609 and rs8050136 was associated with higher fasting glucose levels.ConclusionOur findings indicate that neither the FTO rs9939609 and rs8050136 polymorphisms nor its haplotypes are related to PCOS, but suggest an association between the presence of risk alleles of SNPs rs9939609 and rs8050136 in FTO and glucose levels in women from Southern Brazil.