Lars Forsberg, researcher at the Department of Immunology, Genetics and Pathology, Uppsala University, and responsible for the study, said that they have now tested if there were any lifestyle- or clinical factors that could be linked to loss of the Y chromosome. Out of a large number of factors that were studied, such as age, blood pressure, diabetes, alcohol intake and smoking, they found that loss of the Y chromosome in a fraction of the blood cells was more common in smokers than in non-smokers'.
The association between smoking and loss of the Y chromosome was dose dependent, i.e. loss of the Y chromosome was more common in heavy smokers compared to moderate smokers. In addition, the association was only valid for men who were current smokers. Men who had been smoking previously, but quit, showed the same frequency of cells with loss of the Y chromosome, as men who had never smoked.
The study was published in Science.