title: Genetic polymorphisms in genes related to risk-taking behaviours predicting body mass index trajectory among Mexican American adolescents.
abstract: Obesity is associated with multiple health problems and often originates in childhood. The purpose is to investigate the associations of genetic polymorphisms in genes related to risk-taking behaviours with body mass index (BMI) trajectory over adolescence among Mexican Americans.
  
  
  
  This study included 1229 Mexican American adolescents who participated in a large population-based cohort study in Houston, Texas. BMI data were obtained at baseline and two follow-ups. The median follow-up time was 59 months. Participants were genotyped for 672 functional and tagging variants in genes involved in the dopamine, serotonin and cannabinoid pathways.
  
  
  
  After adjusting for multiple comparisons, three genetic variants, namely, rs933271 and rs4646310 in COMT gene, and rs9567733 in HTR2A gene were significantly associated with BMI growth over adolescence. Using those three variants, we created an allelic score, and the allelic score was associated with BMI growth over adolescence (P < 0.001). With the increase number of variant allele, the rate of BMI growth over adolescence was slower. Finally, we identified another two genetic variants, namely, rs17069005 in HTR2A gene and rs3776511 in SLC6A3A gene were associated with obesity at last follow-up.
  
  
  
  The results suggest that genetic variants in selected genes involved in dopamine and serotonin pathways have noticeable effects on BMI over adolescence.
authors.affiliation: Departments of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Michael and Susan Dell Center for Healthy Living, University of Texas School of Public Health, Austin Regional Campus, Austin, TX, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Wilkinson
authors.affiliation: Departments of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Shen
authors.affiliation: Departments of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Xifeng
authors.initials: X
authors.lastname: Wu
authors.affiliation: Departments of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Wong-Ho
authors.initials: WH
authors.lastname: Chow
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D000483:Alleles; D015992:Body Mass Index; D002648:Child; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D017058:Mexican Americans / Q000235:genetics; D063766:Pediatric Obesity / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D012309:Risk-Taking; D013781:Texas
keywords: Mexican Americans; adolescence; body mass index; genetic polymorphism; risk-taking behaviours