title: Heritabilities of apolipoprotein and lipid levels in three countries.
abstract: This study investigated the influence of genes and environment on the variation of apolipoprotein and lipid levels, which are important intermediate phenotypes in the pathways toward cardiovascular disease. Heritability estimates are presented, including those for apolipoprotein E and AII levels which have rarely been reported before. We studied twin samples from the Netherlands (two cohorts; n = 160 pairs, aged 13-22 and n = 204 pairs, aged 34-62), Australia (n = 1362 pairs, aged 28-92) and Sweden (n = 302 pairs, aged 42-88). The variation of apolipoprotein and lipid levels depended largely on the influences of additive genetic factors in each twin sample. There was no significant evidence for the influence of common environment. No sex differences in heritability estimates for any phenotype in any of the samples were observed. Heritabilities ranged from 0.48-0.87, with most heritabilities exceeding 0.60. The heritability estimates in the Dutch samples were significantly higher than in the Australian sample. The heritabilities for the Swedish were intermediate to the Dutch and the Australian samples and not significantly different from the heritabilities in these other two samples. Although sample specific effects are present, we have shown that genes play a major role in determining the variance of apolipoprotein and lipid levels in four independent twin samples from three different countries.
authors.affiliation: Molecular Epidemiology Section, Department of Medical Statistics and Bioinformatics, Leiden University Center, Leiden, The Netherlands. M.Beekman@LUMC.nl
authors.forename: Marian
authors.initials: M
authors.lastname: Beekman
authors.forename: Bastiaan T
authors.initials: BT
authors.lastname: Heijmans
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Martin
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Pedersen
authors.forename: John B
authors.initials: JB
authors.lastname: Whitfield
authors.forename: Ulf
authors.initials: U
authors.lastname: DeFaire
authors.forename: G Caroline M
authors.initials: GC
authors.lastname: van Baal
authors.forename: Harold
authors.initials: H
authors.lastname: Snieder
authors.forename: George P
authors.initials: GP
authors.lastname: Vogler
authors.forename: P Eline
authors.initials: PE
authors.lastname: Slagboom
authors.forename: Dorret I
authors.initials: DI
authors.lastname: Boomsma
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D016633:Apolipoprotein A-II / Q000097:blood*; D001057:Apolipoproteins E / Q000097:blood* / Q000235:genetics*; D001315:Australia / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology / Q000235:genetics*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D015331:Cohort Studies; D004200:Diseases in Twins / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D013548:Sweden / Q000453:epidemiology
chemical_list: D016633:Apolipoprotein A-II; D001057:Apolipoproteins E; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D008055:Lipids