Here's how genes affect tobacco and alcohol use

A recent study now has discovered several genes associated with an increased use of alcohol and tobacco.

Notably, the use of alcohol and tobacco is closely linked to several diseases, and is a contributing factor in many deaths.

The study, published in the journal Nature Genetics saw involvement of everal research groups around the world, including a group from the Nord-Trøndelag Health Study (HUNT) and the K.G. Jebsen Center for Genetic Epidemiology.

Speaking about it, co author Professor Kristian Hveem, "We discovered several genes associated with an increased use of alcohol and tobacco. We also looked at the correlation between these genes and the risk of developing various diseases and disorders."

The research groups discovered a total of 566 gene variants at 406 different sites in the human genetic material that can be linked to the use of alcohol or tobacco. One hundred fifty of these sites are linked to the use of both tobacco and alcohol.

Alcohol consumption was measured in terms of the number of standard alcohol units. Tobacco use was measured in the number of cigarettes per day.

Hveem said, "The study group that was genetically predisposed to smoking was also genetically predisposed to a number of health problems, including obesity, diabetes, ADHD and various mental illnesses, whereas a genetic risk for alcohol was associated with lower disease risk. This does not imply that consuming more alcohol improves health, but indicates a mechanistic complexity that needs to be investigated further."

The experts reported evidence for the involvement of many natural signalling agents in tobacco and alcohol use, including genes involved in nicotinic, dopaminergic, and glutamatergic neurotransmission which to some extent may provide a biological explanation for why we seek artificial stimuli.

The data that was collected came from a number of studies and included different age categories, societies with different attitudes to the use of drugs and different patterns of alcohol and nicotine use.

However, results showed that the correlation between genetic risk and the development of different disease categories varied little between the population groups.

The research gives new insight into the complexity of genetic and environmental factors that compel some of us to drink and smoke more than others. It is also interesting to note that some of these genes linked to increased use of alcohol, reduce the risk for some diseases.