title: Genetic variation in exon 17 of INSR is associated with insulin resistance and hyperandrogenemia among lean Indian women with polycystic ovary syndrome.
abstract: OBJECTIVE
  Polycystic ovary syndrome (PCOS) is a multigenic disorder, and insulin resistance is one of its hallmark features. Polymorphisms in exon 17 of insulin receptor (INSR) gene are reported to be associated with PCOS. We investigated this association in Indian women and its putative relationship with PCOS associated traits, which has not been explored so far.
  
  
  METHODS
  In this case control study, the polymorphisms were investigated by direct sequencing in 180 women with PCOS and 144 age matched controls. Clinical, anthropometric, biochemical, and hormonal parameters were also estimated.
  
  
  RESULTS
  The silent C/T polymorphism at His1058 in exon 17 of INSR was found to be present in our study population. The polymorphic genotype (CT+TT) was significantly associated with PCOS in lean women (chi(2)=8.493, df=1, P=0.004). It showed association with higher fasting insulin levels (P=0.02), homeostasis model assessment of insulin resistance (P=0.005), free androgen index (P=0.03), and lower quantitative insulin sensitivity check index (P=0.004) in lean PCOS women. No other novel or known polymorphism was identified in exon 17 in this cohort.
  
  
  CONCLUSIONS
  The study shows significant association of C/T polymorphism at His1058 of INSR with PCOS in the lean rather than obese Indian women. Its association with indices of insulin resistance and hyperandrogenemia is also seen in the same group. The findings strengthen the concept that pathogenesis of PCOS is different in lean and obese women.
authors.affiliation: Department of Molecular Endocrinology, National Institute for Research in Reproductive Health, Indian Council of Medical Research (ICMR), Jehangir Merwanji Street, Parel, Mumbai 400012, India. mukherjees@nirrh.res.in
authors.forename: Srabani
authors.initials: S
authors.lastname: Mukherjee
authors.forename: Nuzhat
authors.initials: N
authors.lastname: Shaikh
authors.forename: Sushma
authors.initials: S
authors.lastname: Khavale
authors.forename: Gayatri
authors.initials: G
authors.lastname: Shinde
authors.forename: Pervin
authors.initials: P
authors.lastname: Meherji
authors.forename: Nalini
authors.initials: N
authors.lastname: Shah
authors.forename: Anurupa
authors.initials: A
authors.lastname: Maitra
mesh_terms: D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000235:genetics*; D016022:Case-Control Studies; D004252:DNA Mutational Analysis; D005091:Exons / Q000235:genetics; D005260:Female; D014644:Genetic Variation / Q000502:physiology*; D006801:Humans; D017588:Hyperandrogenism / Q000150:complications / Q000235:genetics* / Q000378:metabolism; D007194:India; D007333:Insulin Resistance / Q000235:genetics*; D009765:Obesity / Q000150:complications / Q000235:genetics / Q000378:metabolism; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000235:genetics* / Q000378:metabolism; D011972:Receptor, Insulin / Q000235:genetics*; D013851:Thinness / Q000150:complications / Q000235:genetics* / Q000378:metabolism; D055815:Young Adult
chemical_list: D015703:Antigens, CD; C435941:INSR protein, human; D011972:Receptor, Insulin