Alpha-1-antitrypsin genetic polymorphism in patients with inflammatory bowel disease: Low frequency of heterozygosity of the Piz variant among patients with ulcerative colitis

Original article


Abdul-Nasser Elzouki, Sten Eriksson, Stefan Lindgren

JMJ Vol. 1, No. 2 (November 2001): 67-71


The pathogenesis of inflammatory bowel disease is enigmatic. Several genetic and environmental factors have been implicated. We studied 137 untreated patients with ulcerative colitis and 100 patients with crohn´s disease, seen at Malm? Universiry Hospital, Sweden during the past 40 years. One (0.o7%) and four patients (4%) were found to be heterozygote for Piz allele of alpha-1-antitrypsin (AAT) deficiency among the ulcerative colitis and crohn´s disease patients, respectively (odd ratio=6.4, 95% confidence interval=1.2-36; p=0.035 and odds ratio= 1.1, 95% confidence interval=0.4-3.1; p=0.821). In the crohn´s disease group, there were no significant differences between the heterozygote and non-Piz carriers in age at onset of disease, sex distribution, site of disease or mean duration of disease (p.o.2 for all comparisons). None of the Piz heterozygote had plasma AAT level below the normal range, through the group mean was lower than that of the non- Piz carriers (p=0.006). In conclusion, it seems unlikely that the Piz gene play an important role in the susceptibility of individuals to crohn´s disease. However, lak of this gene may be implicated in the pathogenesis of ulcerative colitis.

Keywords: antitrypsin, Crohn´s disease, inflammatory bowel disease, protease inhibitors, and ulcerative colitis