IDENTIFICATION OF A CROHNS-DISEASE SPECIFIC TRANSCRIPT WITH POTENTIALAS A DIAGNOSTIC MARKER

Background-A long time goal of the medical research community has been the identification of a reliable and valid marker for Crohn's disease . Aim-To identify differences in the genetic expression patterns of he althy and diseased tissues. Method-The RNA arbitrarily primed polymera se chain reaction (RAP-PCR) procedure was modified to improve its pote ntial to identify clinical markers in heterogeneous RNA populations. R esults-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 sequen ce originates from a unique RNA species of 3.1 kb. Dot blot hybridisat ions clearly showed that this RNA species was specific to Crohn's dise ase. Moreover, its abundance seemed to correlate with the severity of inflammation. Finally, this RNA species was also detected in macroscop ically normal areas from Crohn's disease specimens, suggesting that it appears either early during the disease or at least before severe man ifestations. Conclusion-This finding of a 3.1 kb RNA species permits t he discrimination of Crohn's disease manifestations. Although further clinical work is required, this transcript appears to have definite po tential as a diagnostic marker.