Drinking alcohol can cause cancer by damaging DNA, finds study

Alcohol is responsible for four per cent of cancers in the UK

Alcohol can cause cancer by permanently damaging stem cell DNA, a new study has found.

Links between drinking and cancer are well-documented, however, the science behind this correlation has remained fairly ambiguous until now.

Researchers from the Medical Research Council’s lab of molecular biology at Cambridge University found that alcohol severely damages the DNA of stem cells in the blood and can subsequently lead to the formation of tumours.

When alcohol is broken down in the body it produces a toxic chemical known as acetaldehyde.

The study’s authors conducted their research on a group of mice, who were given ethanol and were subsequently examined to see what effect the acetaldehyde had on their cellular structures.

By conducting chromosome analysis and DNA sequencing, they were able to uncover the level of genetic damage that had been caused as a result of the ethanol.

They found that the chemical gave rise to permanent mutations in the mice’s DNA sequences which could lead to various forms of cancers.

Recent figures estimate that 21,000 cases of cancer in the UK could be avoided if nobody drank alcohol.

“Some cancers develop due to DNA damage in stem cells,” explains lead author Ketan Patel.

“While some damage occurs by chance, our findings suggest that drinking alcohol can increase the risk of this damage.”

The study, which was published in the journal Nature, also looked at how the body defends itself against alcohol.

Enzymes known as aldehyde dehydrogenase (ALDH) break down aldehyde, however, millions of people worldwide lack these key enzymes or possess faulty ones.

Scientists looked at the effect aldehyde had on mice with and without these critical ALDH enzymes and found that those who didn’t have them suffered from four times as much damage to their DNA.

“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,” added 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 defence mechanisms are intact.”

According to Cancer Research UK, who part-funded the research, recent studies reveal that alcohol is responsible for 12,800 cancer cases in the UK each year, 4,800 of which are bowel cancers.

Professor Linda Bauld of the organisation said: “This thought-provoking research highlights the damage alcohol can do to our cells — costing some people more than just a hangover.”