title: Associations of the growth hormone receptor (GHR) gene polymorphisms with adiposity and IGF-I activity in adolescents.
abstract: OBJECTIVE
  To explore the genetic effect of the GH receptor (GHR) on obesity and related metabolic parameters in Hong Kong Chinese adolescents.
  
  
  BACKGROUND
  Obesity is a growing global epidemic. Increasing evidence suggests that the GH-IGF-I axis plays an important role in regulating adiposity and insulin sensitivity.
  
  
  METHODS
  We examined the associations of genetic variants of GHR with serum IGF-I and IGFBP-3 levels as well as obesity-related metabolic traits in Hong Kong Chinese adolescents.
  
  
  METHODS
  Nine hundred and eighty-one randomly selected Hong Kong Chinese adolescents from 14 schools.
  
  
  METHODS
  We genotyped 17 single nucleotide polymorphisms (SNP) at GHR and measured serum IGF-I and IGFBP-3 levels as well as obesity-related metabolic traits including fasting plasma glucose, insulin and lipid levels.
  
  
  RESULTS
  There were significant associations between rs4410646 and the body composition (P = 0.0044) and blood pressure factor scores (P = 0.00017). Carriers of the CC genotype had lower body mass index, percentage body fat, waist and hip circumferences than AC and AA genotype carriers (P = 0.00030-0.0094). There was also association between rs7703713 and the IGF-I activity factor score (P = 0.0033). The GA and AA carriers of rs7703713 had higher serum IGF-I, higher serum IGFBP-3 and higher IGF-I/IGFBP-3 molar ratio (P = 0.00069-0.025). Haplotype analysis did not increase the significance of associations.
  
  
  CONCLUSIONS
  Our results support the role of GHR gene polymorphisms in modulating adiposity and IGF-I activity in adolescents. Examination of interactions of these SNPs with lifestyle, environmental and perinatal factors may provide further insights into their long-term effects on obesity and metabolic risks.
authors.affiliation: Department of Biochemistry, The Chinese University of Hong Kong, The Prince of Wales Hospital, Shatin, Hong Kong SAR, CHINA.
authors.forename: Janice L Y
authors.initials: JL
authors.lastname: Mong
authors.forename: Maggie C Y
authors.initials: MC
authors.lastname: Ng
authors.forename: Georgia S
authors.initials: GS
authors.lastname: Guldan
authors.forename: Claudia H T
authors.initials: CH
authors.lastname: Tam
authors.forename: Heung Man
authors.initials: HM
authors.lastname: Lee
authors.forename: Ronald C W
authors.initials: RC
authors.lastname: Ma
authors.forename: Wing Yee
authors.initials: WY
authors.lastname: So
authors.forename: Gary W K
authors.initials: GW
authors.lastname: Wong
authors.forename: Alice P S
authors.initials: AP
authors.lastname: Kong
authors.forename: Juliana C N
authors.initials: JC
authors.lastname: Chan
authors.forename: Mary M Y
authors.initials: MM
authors.lastname: Waye
mesh_terms: D050154:Adiposity; D000293:Adolescent; D000368:Aged; D000704:Analysis of Variance; D001823:Body Composition; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D009765:Obesity / Q000097:blood / Q000378:metabolism; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D011986:Receptors, Somatotropin / Q000235:genetics*; D014280:Triglycerides / Q000097:blood
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D018972:Insulin-Like Growth Factor Binding Protein 3; D011986:Receptors, Somatotropin; D014280:Triglycerides; D007334:Insulin-Like Growth Factor I; D002784:Cholesterol