Genetic markers and duodenal ulcer.

Serum pepsinogen, alpha 1-antitrypsin (alpha 1-AT) and blood groups were studied as genetic markers in 32 patients with endoscopically proven duodenal ulcer and 44 control subjects with no family history of ulcer disease. Serum pepsinogen was determined by the modified method of Edward et al, alpha 1-AT by single radial immunodiffusion (RID) and phenotyping was carried out by isoelectric focusing (IEF). Duodenal ulcer patients with hyper- pepsinogenemia (28%) and low serum alpha 1-AT (35%) had a dominant blood group O, lower mean age, an early onset of disease, a higher frequency of gastrointestinal (GI) bleeding and ulcer perforation. These parameters were found considerably different in patients with normal serum pepsinogen and alpha 1-AT. Phenotype analysis of alpha 1-AT revealed that four duodenal ulcer patients had partial deficiency of the protease inhibitor and none of the normal exhibited the deficiency pattern. The etiology of the disease appears to be genetic anomaly in 28% of patients while the rest (72%) had ulcers as a result of neuroendocrinological or environmental factors.