UCLA researchers from the Vatche and Tamar Manoukian Division of Digestive Diseases have discovered an innovative approach to diagnose irritable bowel syndrome. This method uses a set of epigenetic profiles as biomarkers and is highly sensitive compared to conventional diagnostic methodologies.
Irritable bowel syndrome (IBS) affects up to 11% of the global population and is largely diagnosed by symptoms criteria. It is associated with significant health and economic burden and decreases quality of life. Surprisingly, there is no consistent genetic expression or biomarker for the accurate diagnosis of IBS. The only commercially available diagnostic antibody test is only about 50% sensitive but highly specific for a subgroup of IBS patients, which limits its widespread use for diagnosis and does not offer much information on treatment planning. Therefore, a highly sensitive, specific and informative diagnostic approach will add great value to clinical care of this multifactorial and heterogeneous disorder.
Many environmental influences associated with IBS, such as stress and diet, can induce epigenetic changes that alter gene expression without changing the genetic sequence. A blood-based diagnostic test using an epigenetic profile to diagnose IBS was developed to improve upon symptom based clinical diagnostic methods. This test was created based on a comparison analysis of epigenetic profiles between healthy individuals and IBS patients. This test has a 77% sensitivity, 91% specificity and a 91% positive predictive value for the diagnosis of IBS. Additional preliminary analyses demonstrate that an epigenetic profile can also distinguish IBS from inflammatory bowel disease (IBD), which can present with symptoms similar to that in IBS, with 100% accuracy. This diagnostic test can potentially also offer insights into patient responses to drug treatments.