Facts about Crohn's disease

Crohn’s disease (CD), a chronic inflammatory condition of the intestinal tract, is affecting people globally. Experts have long suspected that CD represents a collection of related but slightly different disorders.

In a study published in the journal JCI Insight, researchers at the University of North Carolina reported that they have pinpointed a single molecule – microRNA-31 (miR-31) – the levels of which predict whether a patient has subtype 1 or subtype 2 of the disease.

This is important because patients with subtype 1, unlike subtype 2, often do not respond well to medications and develop strictures – extreme narrowing of the gut tube, requiring surgery once it develops. Markers like miR-31 could be useful in the future for clinicians to predict whether a patient should pursue pre-emptive surgery before the condition worsens.

“We are not at the point at which we are able to perform personalized medicine on this, but at the very least we think it can lead to better clinical trial designs,” said Praveen Sethupathy, senior co-author of the study.

Clinical trials have generally grouped all patients together for testing a new therapy for CD, and that has lead to inconsistent results across the group. Using miR-31, researchers potentially could separate individuals with CD into subtypes in order to more accurately determine if a particular drug works for one subtype and not the other.

In the study, the researchers also used a state-of-the-art artificial gut, called an intestinal organoid, which allowed them to culture human biopsy samples while retaining the basic physiology that exists inside a human.

The researchers also used cutting-edge genomic techniques to track the abundance of different molecules in the colon tissue of more than 150 pediatric and adult patients. MicroRNAs control the extent to which a target gene is turned on. They function as negative dials – the greater the abundance of a microRNA, the more a target gene will be suppressed. Data from genomic sequencing technology allowed the researchers to make their miR-31 discovery.