Researchers have identified a rare genetic variation that seems to reduce how much people smoke, offering a fresh clue in the fight against tobacco addiction. The study, published in Nature Communications, looked at nearly 38,000 smokers and found that people with certain variants of a gene called CHRNB3 tend to smoke fewer cigarettes per day compared with those without it.
- The CHRNB3 gene makes part of a nicotine receptor in the brain—the structure through which nicotine produces pleasurable effects that fuel addiction.
- People with one copy of this rare variant smoked about 21 % less (roughly one fewer cigarette per day). Those with two copies smoked roughly 78 % fewer cigarettes.
- The same association showed up in people of Mexican, East Asian and European ancestry, suggesting the finding is robust across different backgrounds.
Scientists think that this change might alter how the nicotine receptor works—possibly making nicotine less rewarding or addictive—but they don’t yet understand the exact biological mechanism.
The big idea is that the gene could point to a new kind of therapy for smoking addiction. If drugs could mimic the effect of this variant (for example, by inhibiting the CHRNB3 protein), they might help smokers cut down or quit. But experts are cautious: it’s too early to say whether such treatments can be developed, whether they’d be safe, or how effective they might be in real life. More research is needed before this finding can translate into a treatment.
In short: Scientists found a genetic variant that makes some people smoke less, which could help inspire future therapies to fight nicotine addiction—but there’s still a long way to go before that becomes reality.
Rajagopal, V.M., Ziyatdinov, A., Joseph, T. et al. Rare coding variants in CHRNB3 associate with reduced daily cigarette smoking across ancestries. Nat Commun 17, 1654 (2026). https://doi.org/10.1038/s41467-026-68825-2
