title: Genetic and environmental influences on waist-to-hip ratio and waist circumference in an older Swedish twin population.
abstract: OBJECTIVE
  To investigate the genetic and environmental influences on waist-to-hip ratio (WHR) and waist circumference (WC) measurements in males and females.
  
  
  METHODS
  Measurements taken from 1989-1991 as part of The Swedish Adoption/Twin Study of Aging (SATSA) were used for analysis. The SATSA sample contains both twins reared together as well as twins reared apart.
  
  
  METHODS
  322 pairs of twins (50 identical, 82 fraternal male pairs and 67 identical, 123 fraternal female pairs); age range: 45-85y (average age, 65y).
  
  
  METHODS
  Waist-to-hip ratio (WHR), waist circumference (WC) and body mass index (BMI).
  
  
  RESULTS
  In males, additive genetic effects were found to account for 28% of the variance in WHR and 46% of the variance in WC. In females, additive genetic effects were found to account for 48% of the variance in WHR and 66% of the variance in WC. The remaining variance in males was attributed to unique environmental effects (WHR, 72%; WC, 54%) and in females the remaining variance was attributed to unique environmental effects (WHR, 46%; WC, 34%) and age (WHR, 6%). When BMI was added into these models it accounted for a portion of the genetic and environmental variance in WHR, and over half of the genetic and environmental variance in WC.
  
  
  CONCLUSIONS
  There are both genetic and environmental influences on WHR and WC, independent of BMI in both males and females, and the differences between the sexes are significantly different.
authors.affiliation: Department of Biobehavioral Health and Center for Developmental and Health Genetics, The Pennsylvania State University, University Park 16802, USA. tnelson@sph.unc.edu
authors.forename: T L
authors.initials: TL
authors.lastname: Nelson
authors.forename: G P
authors.initials: GP
authors.lastname: Vogler
authors.forename: N L
authors.initials: NL
authors.lastname: Pedersen
authors.forename: T P
authors.initials: TP
authors.lastname: Miles
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001824:Body Constitution / Q000235:genetics*; D015992:Body Mass Index; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008957:Models, Genetic; D015999:Multivariate Analysis; D009765:Obesity / Q000235:genetics*; D012737:Sex Factors; D013548:Sweden