An international research team has identified a genetic variant that reduces the number of cigarettes smoked and lowers the risk of nicotine addiction. The variant in the CHRNA5 gene, which codes for a subunit of the nicotinic receptor, influences a lesser 'delight' in nicotine and could become a target for new addiction treatment therapies.
Discovery of the CHRNA5 Gene
Researchers identified a specific variant (rs16969968) in the CHRNA5 gene, which codes for the alpha-5 subunit of the nicotinic receptor. Individuals possessing this variant show a lower demand for nicotine and smoke fewer cigarettes per day on average, which directly translates to a lower risk of developing addiction and tobacco-related diseases.
Receptor Mechanism of Action
The genetic variant affects the function of the nicotinic receptor in the brain, modifying how neurons respond to nicotine. This leads to a weakening of the positive reinforcement that typically drives the addiction. Individuals with this mutation experience less pleasure from smoking, which naturally discourages them from reaching for another cigarette and makes it easier to quit the habit.
New Therapeutic Targets
The discovery opens the way for developing new drugs that mimic the action of the protective genetic variant. Therapies could modulate the activity of the alpha-5 nicotinic receptor, reducing the feeling of satisfaction from smoking and helping to fight nicotine cravings. This is an alternative to current methods, such as nicotine replacement therapy.
Study Scale and Methodology
The results are based on an analysis of genetic data from biobanks and consortia, encompassing a total of over 800,000 individuals of European descent. Scientists utilized techniques <przypis title=
A groundbreaking genetic study sheds new light on the biological basis of tobacco addiction. An international team of scientists discovered that a specific variant in the CHRNA5 gene, known as rs16969968, acts like an internal anti-addiction shield. Individuals carrying this genetic variant smoke fewer cigarettes per day on average and show a lower risk of developing full-blown nicotine addiction. The study, published on February 24, 2026, in the prestigious journal "Nature Communications", analyzed data from over 800,000 participants, making it one of the largest undertakings in behavioral genetics. The CHRNA5 gene codes for a subunit of the nicotinic receptor, which plays a key role in communication between neurons in the so-called brain reward system. Since the 1990s, it has been known that nicotinic receptors are the primary site of action for nicotine, the substance responsible for the development of tobacco addiction. The mechanism of action of the discovered variant involves modifying the receptor's function. In the protective variant, the alpha-5 nicotinic receptor exhibits an altered response to nicotine stimulation.