It’s widely known that alcohol isn’t exactly great for your body, especially when consumed in excess. But according to a new study from researchers at the MRC Laboratory of Molecular Biology in Cambridge, it can actually affect your genetics. The results found that alcohol can damage DNA in stem cells, which helps explain why drinking increases your risk of cancer.
The researchers gave diluted alcohol to mice, then used chromosome analysis and DNA sequencing to examine the genetic damage caused by acetaldehyde, which is a chemical produced when our bodies process alcohol. Their findings showed that acetaldehyde can break and damage DNA within blood stem cells, resulting in rearranged chromosomes and permanently altered DNA sequences within the affected cells.
When stem cells become faulty, they can give rise to cancer. This is why it’s important for scientists to study how the DNA within stem cells becomes damaged. These new findings help us to understand how drinking alcohol increases the risk of getting 7 types of cancer, including common forms such as breast and bowel.
“Some cancers develop due to DNA damage in stem cells,” explains Professor Ketan Patel, lead author of the study and scientist at the MRC Laboratory of Molecular Biology. “While some damage occurs by chance, our findings suggest that drinking alcohol can increase the risk of this damage.”
Beyond just looking at how alcohol damages DNA, the researchers also examined how the body attempts to protect itself against damage caused by alcohol. They found that the first line of defense is a family of enzymes called aldehyde dehydrogenases (ALDH), which breakdown the harmful acetaldehyde into acetate, which our cells can use as a source of energy.
When mice lacking the ALDH enzyme were given alcohol, it was found that they suffered four times as much DNA damage in their cells compared to normal mice. Around the world, millions of people either lack these enzymes or carry faulty versions of them.
Cells also use a variety of DNA repair systems, which allow them to fix and reverse certain types of DNA damage. But they don’t always work and some individuals have mutations which prevent their cells from carrying out these repairs effectively.
“Our study highlights that not being able to process alcohol effectively can lead to an even higher risk of alcohol-related DNA damage and therefore certain cancers,” explains Patel. “But it’s important to remember that alcohol clearance and DNA repair systems are not perfect and alcohol can still cause cancer in different ways, even in people whose defense mechanisms are intact.”