Application of the a priori methods for genetico-mathematical analysis of the inheritance pattern of ulcer disease.

The a priori methods were used to perform a detailed genetico-mathematical analysis of the pattern ulcer disease is inherited. The study included families of 351 probands. Of these, 267 were with duodenal ulcer, 57 with gastric ulcer type II, and 27 with gastric ulcer type III. The types of gastric ulcer were defined according to the classification proposed by H. Johnson. The cases of duodenal ulcer were also analyzed depending on the type of familial predisposition of the patients. The results from Bernstein's a priori method and Li's a priori correction method exclude autosomal recessive pattern of inheritance of the three types of peptic ulcer, not even in the families with healthy but hereditarily predisposed parents. On the other hand, the difference between the numbers of actually observed and theoretically predicted sick children in all groups studied, including those in the families with one sick parent, found by applying the Hogben modification of Bernstein's a priori method, is not consistent with an autosomal dominant pattern of inheritance. Nor is this inheritance pattern consistent with the finding that there are no essential differences between the quantitative parameters of the families with one or two sick parents. It is, therefore, concluded that this disease is not possible to be passed down in generations in a monogenic mode.