[Problems in the genetics of peptic ulcer. I. The nature of the inheritance and an analysis of different forms of the disease].

The analysis of literary data on the genetic investigation of duodenal ulcer is given. The investigation proper represents the analysis of 537 pedigree probands with various forms of duodenal ulcer and of 600 families of the control group. Basing on the analysis of distribution of frequency of forms of the disease, segregation analysis, as well as the distribution of forms of duodenal ulcer depending on the sex and age of the manifestation, the discrepancy is demonstrated of the opinion that duodenal ulcer is a monogenic disease, and a conclusion is drawn about the polygen conditionality of genetic component of various forms. The data have been obtained testifying in favour of a considerable heterogeneity of the duodenal ulcer and also the importance of the contribution to the genetic factors in the realization of different forms of the disease, which are approximately 60%. Some difficulties are illustrated, arising during the analysis of multifactorial disease, and the necessity is demonstrated of accounting its certain features (e.g. sex, the age of manifestation) during the interpretation of the results obtained.