Ontology highlight
ABSTRACT: Background
Blood levels of gamma-glutamyl transferase (GGT) are used as a marker for (heavy) alcohol use. The role of GGT in the anti-oxidant defense mechanism that is part of normal metabolism supposes a causal effect of alcohol intake on GGT. However, there is variability in the response of GGT to alcohol use, which may result from genetic differences between individuals. This study aimed to determine whether the epidemiological association between alcohol intake and GGT at the population level is necessarily a causal one or may also reflect effects of genetic pleiotropy (genes influencing multiple traits).Methods
Data on alcohol intake (grams alcohol/day) and GGT, originating from twins, their siblings and parents (N=6465) were analyzed with structural equation models. Bivariate genetic models tested whether genetic and environmental factors influencing alcohol intake and GGT correlated significantly. Significant genetic and environmental correlations are consistent with a causal model. If only the genetic correlation is significant, this is evidence for genetic pleiotropy.Results
Phenotypic correlations between alcohol intake and GGT were significant in men (r=.17) and women (r=.09). The genetic factors underlying alcohol intake correlated significantly with those for GGT, whereas the environmental factors were weakly correlated (explaining 4-7% vs. 1-2% of the variance in GGT respectively).Conclusions
In this healthy population sample, the epidemiological association of alcohol intake with GGT is at least partly explained by genetic pleiotropy. Future longitudinal twin studies should determine whether a causal mechanism underlying this association might be confined to heavy drinking populations.
SUBMITTER: van Beek JHDA
PROVIDER: S-EPMC3909645 | biostudies-literature | 2014 Jan
REPOSITORIES: biostudies-literature
van Beek Jenny H D A JHDA de Moor Marleen H M MHM Geels Lot M LM Sinke Michel R T MRT de Geus Eco J C EJC Lubke Gitta H GH Kluft Cornelis C Neuteboom Jacoline J Vink Jacqueline M JM Willemsen Gonneke G Boomsma Dorret I DI
Drug and alcohol dependence 20130927
<h4>Background</h4>Blood levels of gamma-glutamyl transferase (GGT) are used as a marker for (heavy) alcohol use. The role of GGT in the anti-oxidant defense mechanism that is part of normal metabolism supposes a causal effect of alcohol intake on GGT. However, there is variability in the response of GGT to alcohol use, which may result from genetic differences between individuals. This study aimed to determine whether the epidemiological association between alcohol intake and GGT at the populat ...[more]