Do you think you're sexy when smoking? Think more. I am not talking about deadly issues connected to smoking, like heart attack, stroke, chronic bronchitis, emphysema, and cancers. Smoking can really impair your sex life, cause what's attractive in being impotent, sterile, wrinkled, yellowed skinned and toothed, having a bad breath, being blind because of earlier age-related macular degeneration, coughing, having decreased taste and smell, dermatitis, and a premature baldness?

Not to mention what hurts a woman more: her breasts, the main sign of feminine beauty. Previous researches showed that smoking increases the level of breast ptosis (sagging), as it breaks down a skin protein called elastin, which gives youthful skin its elastic appearance and supports the breast.

But a new research published by the journal "Cancer Epidemiology, Biomarkers and Prevention" comes with an even more alarming perspective: in women with a specific gene makeup, smoking can cause breast cancer.

The team led by Christine Ambrosone, PhD, Cancer Prevention and Population Sciences Program, Roswell Park Cancer Institute (RPCI) and Jenny Chang-Claude, PhD, Professor in Epidemiology at University of Heidelberg, made a meta-analysis of 10 of the 13 researches published in the last 10 years connecting genetics, smoking and the level of breast cancer risk in 4,889 premenopausal and 7,033 postmenopausal women.

There was a strong connection between breast cancer risk, smoking, and the gene NAT2 encoding the enzyme N-acetyltransferase 2 (NAT2). This enzyme degrades aromatic amines, main cancer tobacco chemicals, and the resulting products are easily eliminated from the body. The variations in this gene result in a more rapid or slower eliminations of the carcinogen chemicals; people with slower enzyme are more exposed to subsequent development of breast cancer.

The research connected the number of years of smoking, the number of daily smoked cigarettes and the possession of a slow NAT2 to a boosted risk of breast cancer.

"These results, analyzing all studies to date, indicate that subgroups of women defined by genetic predisposition are at higher risk of breast cancer if they are exposed to tobacco smoke. In fact, smoking is likely to play an important role in the development of breast cancer for about 50-60% of the populations from European descent who have a form of the NAT2 gene that gets rid of aromatic amines more slowly than the rest of the population," said Ambrosene.