IBS is a common condition world-wide, affecting around 1 in 10 people and causing a wide range of symptoms including abdominal pain, bloating and bowel dysfunction that can significantly affect people’s lives. Diagnosis is usually made after considering other possible conditions (such as Crohn’s disease or bowel cancer), with clinical tests coming back ‘normal’. The condition often runs in families and is also more common among people who are prone to anxiety. The causes of IBS are not well understood, but an international team of researchers has now identified several genes that provide clues into the origins of IBS.
Researchers from the Kennedy Institute of Rheumatology at Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS) joined the research team which included more than 40 institutions. Coordinated by scientists in the UK and Spain, they looked at genetic data from 40,548 people who suffer with IBS from the UK Biobank and 12,852 from the Bellygenes initiative (a world-wide study aiming to identify genes linked to IBS) and compared them to 433,201 people without IBS (controls), focusing on individuals of European ancestry. The findings were repeated with de-identified data from the genomics company 23andMe Inc., provided by customers who have consented to research, by comparing 205,252 people with IBS to 1,384,055 controls.
The results, published in Nature Genetics, showed that overall, heritability of IBS (how much your genes influence the likelihood of developing a particular condition) is quite low, indicating the importance of environmental factors such as diet, stress and patterns of behaviour that may also be shared in the family environment.