In a population survey, the point prevalence of duodenal ulcer disease (DUD) was found to be 11.98 percent which is the highest prevalence rate so far reported in the literature. The prevalence of duodenal ulcer dyspepsia in the first degree relatives of groups of subjects with proven duodenal ulcer, non ulcer dyspepsia (NUD) (duodenal ulcer dyspepsia but without evidence of ulcer at endoscopy) and normal healthy control (HC), all matched by age and sex and all from the population with the high prevalence of duodenal ulcer disease, were studied. Both DUD and NUD subjects had a significantly higher family history of duodenal ulcer dyspepsia than the control subjects.