Scientists Find That Smoking Alters Our Genes
We’ve known for decades that smoking alters our lungs, and now scientists are discovering how it changes our genes.
Though we inherit our genetic makeup from our parents, the expression or activity of our genes can be changed by aging, environmental factors (e.g., toxins), and lifestyle habits such as smoking.
These changes to genetic activity are called epigenetic modifications. Researchers have been studying epigenetic alterations in people who smoke and in those who use non-smoke tobacco. They found that several health problems associated with smoking, such as diabetes and cancer, are linked to genes that are modified by smoking.
Researchers discovered many genetic modifications in individuals who use tobacco. However, none of these epigenetic changes were found in users of non-smoke tobacco.
“This means that the epigenetic modifications are likely not caused by substances in the tobacco, but by the hundreds of different elements that are formed when the tobacco is burnt,” said lead researcher Asa Johansson, Uppsala University.
There are over 4,000 chemical compounds created by burning tobacco. Not all of them are harmful but 69 of them are known carcinogens. For instance, cigarette smoke contains nitrogen oxides, carbon monoxide, ammonia, methanol, butane, and hydrogen cyanides.
Previous statistics show that smoking increases a person’s risk for certain forms of cancer, type 2 diabetes, and that it compromises the immune system and sperm quality. Results from the Uppsala research supports these statistics. The scientists noted that the genes altered by smoking include those that increase risk for these same health issues and diseases.
“Our results therefore indicate that the increased disease risk associated with smoking is partly caused by epigenetic changes. A better understanding of the molecular mechanism behind diseases and reduced body function might lead to improved drugs and therapies in the future,” says Johansson.
This study was published in a recent volume of Human Molecular Genetics.