Double Whammy Gene
Three separate teams of scientists say that one gene is linked both to an addiction to smoking and to cancer. People with this gene are more prone to cancer than those without it. In addition, those with the gene smoke more and find it much more difficult to quit than those without the gene. From Seth Borenstein at the AP:
A smoker who inherits this genetic variation from both parents has an 80 percent greater chance of lung cancer than a smoker without the variants, the researchers reported. And that same smoker on average lights up two extra cigarettes a day and has a much harder time quitting than smokers who don’t have these genetic differences. The three studies, funded by governments in the U.S. and Europe, is being published Thursday in the journals Nature and Nature Genetics.
It’s not until the 7th paragraph that one detail becomes clear.
The studies’ authors disagreed on whether the set of variants directly increased the risk of lung cancer or did so indirectly by causing more smoking that led to the cancer.
To know this, they’d need two control groups – one without the gene, subdivided into two sub-groups, one that smokes and one that doesn’t, and a second control group – with the gene, subdivided the same way. That, apparently, wasn’t done.
However, certain oddities do become a bit more understandable:
These oddities include why there are 100-year-old smokers who don’t get cancer and people who light up an occasional cigarette and don’t get hooked.
Other deficiencies in the studies were noted.
The studies mostly looked at smokers and ex-smokers _ although two of the studies also looked at several hundred nonsmokers. The research only involved white people of European descent. People of Asian and African descent will be studied soon and may yield quite different results, scientists said. Smoking-related diseases worldwide kill about one in 10 adults, according to the World Health Organization.