Identification of a Crohn's disease specific transcript with potential as a diagnostic marker

A long time goal of the medical research community has been the identification of a reliable and valid marker for Crohn's disease.

To identify differences in the genetic expression patterns of healthy and diseased tissues.

The RNA arbitrarily primed polymerase chain reaction (RAP-PCR) procedure was modified to improve its potential to identify clinical markers in heterogeneous RNA populations.

With this procedure, a 1065 bp PCR product associated with the inflammation that occurs in Crohn's disease was identified, cloned and sequenced. Northern blot hybridisations showed that this novel sequence originates from a unique RNA species of 3.1 kb. Dot blot hybridisations clearly showed that this RNA species was specific to Crohn's disease. Moreover, its abundance seemed to correlate with the severity of inflammation. Finally, this RNA species was also detected in macroscopically normal areas from Crohn's disease specimens, suggesting that it appears either early during the disease or at least before severe manifestations.

This finding of a 3.1 kb RNA species permits the discrimination of Crohn's disease manifestations. Although further clinical work is required, this transcript appears to have definite potential as a diagnostic marker.