In a recent issue of Addiction, Sobczyk-Kopciol et al. [1] reported an association between the first intron tagging variant rs9939609 in the obesity-predisposing fat mass and obesity-associated (FTO) gene (OMIM no. 610966) and both alcohol consumption and alcohol dependence. Interestingly, the genotype generally associated with elevated risk of obesity [2], acute coronary syndrome [3], some types of cancer [4], end-stage renal disease [5] or overall mortality [6][in all cases at least partially independently on body mass index (BMI)] was associated with lower ethanol consumption, and was less common in alcohol-dependent individuals compared to healthy controls.
Despite the large number of individuals included (6584), an important limitation of the original study [1] is the lack of the confirmatory study. Even large studies are prone to type I error (false positive), and their results need to be replicated [7,8].
To confirm the results by Sobczyk-Kopciol et al. [1], we analysed self-reported alcohol intake (recorded in a standardized interview) and the first intron tagging single nucleotide polymorphisms (SNPs) (rs17817449 or rs9939609; both occur in almost 100% linkage disequilibrium [9]) in three large independent cohorts. We used the Czech post-MONItoring of trends and determinants in Cardiovascular disease (MONICA) study (2559 individuals, examined twice within 3 years) [9], the Czech part of the Health, Alcohol and Psychosocial factors In Eastern Europe (HAPIEE) study (6681 individuals) [10], and a study of the self-contained population of 948 Sorbs in Germany [11]. Finally, 201 Czech patients with alcoholic liver cirrhosis were also genotyped. Data were analysed using logistic regression with the additive mode of inheritance and adjustment for age and gender. > > > > Read More
