title: Total and regional fat distribution is strongly influenced by genetic factors in young and elderly twins.
abstract: OBJECTIVE
  Indirect estimates of obesity such as BMI seem to be strongly influenced by genetic factors in twins. Precise measurements of total and regional fat as determined by direct techniques such as DXA scan have only been applied in a few twin studies. The aim of the present study was to estimate the heritability (h(2)) of total and regional fat distribution in young and elderly Danish twins.
  
  
  METHODS
  Monozygotic (108) and dizygotic (88) twins in two age groups (25 to 32 and 58 to 66 years) underwent anthropometric measurements and DXA scans. Intraclass correlations and etiologic components of variance were estimated for total and regional fat percentages using biometric modeling.
  
  
  RESULTS
  The intraclass correlations demonstrated higher correlations for all fat percentages among monozygotic twins as compared with dizygotic twins. The biometric modeling revealed a major genetic component (h(2)) of total (h(2)(young) = 0.83, h(2)(elderly) = 0.86) and regional fat percentages (trunk, h(2)(young) = 0.82, h(2)(elderly) = 0.85; lower body, h(2)(young) = 0.83, h(2)(elderly) = 0.81; and trunk/lower body, h(2)(young) = 0.83, h(2)(elderly) = 0.71) in both the young and elderly twins.
  
  
  CONCLUSIONS
  The h(2) estimates emphasize that body fat and distribution as determined by DXA scan are under extensive genetic control.
authors.affiliation: Steno Diabetes Center, Gentofte, Denmark.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Malis
authors.forename: Eva L
authors.initials: EL
authors.lastname: Rasmussen
authors.forename: Pernille
authors.initials: P
authors.lastname: Poulsen
authors.forename: Inge
authors.initials: I
authors.lastname: Petersen
authors.forename: Kaare
authors.initials: K
authors.lastname: Christensen
authors.forename: Henning
authors.initials: H
authors.lastname: Beck-Nielsen
authors.forename: Arne
authors.initials: A
authors.lastname: Astrup
authors.forename: Allan A
authors.initials: AA
authors.lastname: Vaag
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000033:anatomy & histology*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000886:Anthropometry; D001699:Biometry; D001823:Body Composition; D050218:Body Fat Distribution; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000235:genetics*; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic