Is IBS Hereditary? Scientists Investigate the Influence of DNA on Irritable Bowel Syndrome

Gastrointestinal diseases may not be solely related to a person's diet. A new study reveals that genetics could significantly affect GI disorders such as irritable bowel syndrome.

What is Irritable Bowel Syndrome?

Irritable bowel syndrome (IBS) is a group of symptoms that affect the gastrointestinal (GI) tract. This is a common condition characterized by discomfort in the abdomen and changes in bowel movements.

People who suffer from IBS experience abdominal discomfort, which can occur in the form of cramping, sharp pain, distention, bloating, fullness, or even a burning sensation. The pain can be triggered by emotional stress, eating specific foods, constipation, or diarrhea. Other symptoms unrelated to the GI tract include sleep disturbances, migraine headaches, fibromyalgia, anxiety, and chronic pelvic pain.

Many people experience occasional symptoms of IBS. However, the syndrome is more likely to develop in women, people under age 50, and those suffering from mental health issues.

Experts still cannot identify the exact cause of irritable bowel syndrome, although some factors appear to play a role in developing this condition. These include muscle contraction in the intestine, early life stress, changes in gut microbes, severe bacterial or viral infection, or issues in the nervous system.

Doctors will look for patterns in a patient's symptoms to diagnose IBS. They may also review their medical and family history or perform physical exams. In treating IBS, doctors may prescribe certain medicines and probiotics. They may also recommend lifestyle and diet changes and mental health therapies.

Is IBS Hereditary?

In a 2021 study published in Cell Genomics, the researchers reported the particular DNA characteristics in people who experience higher or lower stool frequency. The stool frequency is defined by the number of daily bowel movements and is recorded based on the questionnaire.

To conduct the research, the scientists gathered data from 167,875 people from the UK, the Netherlands, Belgium, Sweden, and the U.S. The collected data were used to compare their genetic makeup with their answers to questions regarding their stool frequency.

The researchers assigned a numerical polygenic score to their genetic findings. This value explains the likelihood of developing an altered stool frequency. According to the research team, they found evidence of a common genetic background related to both stool frequency and the development of irritable bowel syndrome. They discovered that individuals with high polygenic scores are up to 5 times more likely to develop IBS with diarrhea than the rest of the population.

As Dr. Rudolph A. Bedford from Providence Saint John's Health Center in Santa Monica, California, explained, gaining a better insight into the link between genetics and IBS could hold the key to better therapies. However, medicine professor Emeran Mayer from UCLA Brain Gut Microbiome Center also reminds us that although DNA may play a minimal role in the overall condition, there are still behavioral and lifestyle factors that are more significant and that can be adjusted.