Scientists have identified chemical changes in the DNA of patients with inflammatory bowel diseases that could improve screening for the conditions

The CNAG has participated in an international study, coordinated by researchers in the Centre for Genomic and Experimental Medicine (University of Edinburgh) which has detected DNA changes in blood samples, paving the way for simple tests to aid diagnosis of patients suffering from inflammatory bowel diseases.


Inflammatory bowel diseases (IBD) are long-term conditions caused by inflammation of the gut which causes painful abdominal cramps, recurrent diarrhea, weight loss and extreme tiredness. The same symptoms can occur in Crohn’s disease, ulcerative colitis and other bowel conditions, making it difficult for doctors to determine which illness a patient is suffering from. The diseases are currently diagnosed based on analysis of blood and stool samples, however an invasive endoscopy which requires hospitalisation, is usually required to confirm diagnosis.


240 samples analysed

The study, published in Nature Communications, analysed DNA samples from 240 people newly diagnosed with IBD and found that chemical signatures in patients’ DNA (known as epigenetic changes) were different from those in healthy people. Identifying these chemical changes in the DNA of patients with IBD that could improve screening and diagnosis for these conditions, and also shed light on how the diseases develop and could reveal new approaches to treatments. The CNAG, represented by the authors Marta Gut, Simon Heath and Ivo Gut, contributed with the sequencing and analysis of high resolution DNA methylomes of a selected subset of patients and controls to refine the most discriminating differentially methylated positions of the genome that can then be used as blood-based biomarkers for IBD. 


Experts say the findings could lead to a simple blood test to screen people who show symptoms of the diseases. People who do not have the signatures in their DNA could be spared further tests, which can be invasive and require hospital care. Results from the test could help doctors tailor therapies specifically for each patient, and can also reveal clues to a patient’s longer term prognosis.


The study has been funded by the European Union FP7 grants: IBD-BIOM; IBD-Character.


Work of reference

Integrative epigenome-wide analysis demonstrates that DNA methylation may mediate genetic risk in inflammatory bowel disease