According to the researchers, the DNA variant, found in the DNMT3B gene and common in people of European and African origin, increases the likelihood of developing nicotine addiction and developing lung cancer.
The new study by Dr. Dana Hancock of RTI International’s team is the largest nicotine addiction study to date. It involved over 38 (from 600 different studies) former and current smokers from the United States, Iceland, Finland and the Netherlands.
The authors analyzed the genomes of participants, looking for genes correlated with nicotine addiction. Among other things, they confirmed that the three genes that make up the CHRNA5-CHRNA3-CHRNB4 chromosomal region are actually related to smoking, which was previously suspected.
In addition, it turned out that there was another gene that could be strongly associated with nicotine addiction. It is the DNMT3B gene coding for the DNA methyltransferase protein. One variant of this gene was clearly associated with an increased risk of developing nicotine addiction, including severe addiction.
In addition, it turned out that people with this variant of the DNMT3B gene have a greater tendency to develop squamous cell lung cancer.
“This new discovery widens the range of known genetic factors that have been proven to influence nicotine addiction,” says Dr. Hancock. – The gene variant we identified is very common – it occurs in 44 percent of Europeans and Americans of European descent, and 77 percent. African Americans. We have found that it exerts a significant influence on the regulation of genes in the human brain, especially in the cerebellum, which has so far been overlooked in addiction research.
According to the World Health Organization, nearly 1 billion people on Earth smoke cigarettes. There are approximately 6 million premature deaths from smoking each year; a smoker in the world dies every six seconds.