title: FTO Gene Variants Are Associated with PCOS Susceptibility and Hyperandrogenemia in Young Korean Women.
abstract: BACKGROUND
  The fat mass and obesity-associated (FTO) gene is associated with obesity and type 2 diabetes mellitus. Obesity and insulin resistance are also common features of polycystic ovary syndrome (PCOS). Therefore, the FTO gene might be a candidate gene for PCOS susceptibility. The aim of the present study was to evaluate the effects of FTO gene variants on PCOS susceptibility and metabolic and reproductive hormonal parameters.
  
  
  METHODS
  We recruited 432 women with PCOS (24±5 years) and 927 healthy women with regular menstrual cycles (27±5 years) and performed a case-control association study. We genotyped the single nucleotide polymorphisms rs1421085, rs17817449, and rs8050136 in the FTO gene and collected metabolic and hormonal measurements.
  
  
  RESULTS
  Logistic regression revealed that the G/G genotype (rs1421085, 1.6%), the C/C genotype (rs17817449, 1.6%), and the A/A genotype (rs8050136, 1.6%) were strongly associated with an increased risk of PCOS (odds ratio, 2.551 to 2.559; all P<0.05). The strengths of these associations were attenuated after adjusting for age and BMI. The women with these genotypes were more obese and exhibited higher free androgen indices (P<0.05) and higher free testosterone levels (P=0.053 to 0.063) compared to the other genotypes. However the significant differences disappeared after adjusting for body mass index (BMI). When we analyzed the women with PCOS and the control groups separately, there were no significant differences in the metabolic and reproductive hormonal parameters according to the FTO gene variants.
  
  
  CONCLUSIONS
  The rs1421085, rs17817449, and rs8050136 variants of the FTO gene were associated with PCOS susceptibility and hyperandrogenemia in young Korean women. These associations may be mediated through an effect of BMI.
authors.affiliation: Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Do Kyeong
authors.initials: DK
authors.lastname: Song
authors.affiliation: Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Hyejin
authors.initials: H
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Jee-Young
authors.initials: JY
authors.lastname: Oh
authors.affiliation: Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Hong
authors.affiliation: Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Yeon-Ah
authors.initials: YA
authors.lastname: Sung
keywords: FTO; Hyperandrogenism; Polycystic ovary syndrome