Crohn disease: Susceptibility and disease heterogeneity revealed by HLA genotyping

Predisposition to Crohn disease (CD) seems to be genetically determined bur , though several reports on tile matter, the association between HLA antige ns and the disease is still controversial. PCR-SSP high resolution typing i n 107 CD patients, and in subgroups selected according to clinical features , showed a positive association with the rare haplotype DRB1*07, DQB1*0303 both in the overall patients (p = 0.002; pc = ns) and in the subgroup of no nfistulized patients (p = 0.0008; pc = 0.032). Moreover, tile protective ro le of the haplotype DRB1*03, DQB1*0201 (p = 0.029) was confirmed also in It alian patients, whereas no strong association with HLA class I alleles has been found. In addition, variability of the HLA alleles frequency in CD sub groups was observed, supporting the hypothesis of a genetic heterogeneity o f thr disease and suggesting that HLA alleles distribution in selected grou ps may allow to identify patients with probably different prognosis or asso ciated complications. (C) American Society for Histocompatibility and Immun ogenetics, 2001. Published by Elsevier Science Inc.