Studies yield new insights into the genetic etiology of tobacco and alcohol use

In the journal Nature Genetics, 44 researchers collaborated on research into the genetic etiology of tobacco and alcohol use. According to the study authors, tobacco and alcohol use are leading causes of mortality that influence risk for many complex diseases and disorders. They are heritable and etiologically related behaviours that have been resistant to gene discovery efforts.
In sample sizes up to 1.2 million individuals, the researchers discovered 566 genetic variants in 406 loci associated with multiple stages of tobacco use (initiation, cessation, and heaviness) as well as alcohol use, with 150 loci evidencing pleiotropic association (producing or having multiple effects from a single gene). Smoking phenotypes were positively genetically correlated with many health
conditions, whereas alcohol use was negatively correlated with these conditions, such that increased genetic risk for alcohol use is associated with lower disease risk.
The researchers report evidence for the involvement of many systems in tobacco and alcohol use, including genes involved in nicotinic, dopaminergic, and glutamatergic neurotransmission. They state that their results provide a solid starting point to evaluate the effects of these loci in model organisms and more precise substance use measures.
Source: Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use. Liu M, Jiang Y, Wedow R, Li Y, Brazel DM, Chen F, Datta G, Davila-Velderrain J. Nat Genet. 2019 Jan
14.