Thousands of genetic links found for tobacco and alcohol use

A group of international researchers identified more than 2,300 genes predicting alcohol and tobacco use after analyzing data from more than 3.4 million people. The Netherlands Twin Register (NTR) from Vrije Universiteit Amsterdam (VU) contributed to the results. Their data was used to look if genes exist that contribute to the initiation of drinking alcohol or smoking tabaco, the onset of regular use and the amount consumed. Most of these genes were similar among people with European, African, American and Asian ancestries. Roughly a fifth of the participants contributing data to the analysis were from non-European ancestries, which increases the relevance of these findings to a diverse population and represents the largest most diverse genetic study on smoking and drinking behaviors to date. The results are published in Nature.

Alcohol and tobacco use are associated with approximately 15% and 5% of deaths worldwide, respectively, and are linked with chronic conditions like cancer and heart disease. The environment and culture can affect a person’s use and the likelihood of becoming addicted to these substances, but genetics is also a contributing factor.

Genetic risk
The researchers also constructed genetic risk scores (the weighted sum of all risk gene variants) to determine whether people have an increased risk of smoking/drinking. Founder of the NTR and VU-professor Dorret Boomsma and VU-researcher Jouke-Jan Hottenga expect that within two to three years these genetic risk scores could be refined and become part of a more specific routine care for individuals.

Machine learning techniques
Using machine learning techniques, researchers Gretchen Saunders and Scott Vrieze (University of Minnesota) identified genes that were associated with these behaviors and found that there was a striking similarity in the genes related to alcohol and tobacco use behaviors between the different geographic groepen, with 80% of the variants showing consistent effects across the studied populations. While some genetic variants had different effects across ancestries, the genes associated with alcohol and tobacco use were largely consistent between various ancestries.