Genetico-mathematical analysis of the inheritance pattern of peptic ulcer disease. II. Method of simple registration. Assessment of the direct methods of Weinberg.

The inheritance pattern of ulcer disease was analyzed by means of the method of simple registration. We also studied comparatively and assessed all direct methods of Weinberg using the coefficients of genetic proportion calculated by them as a criterion at complete inclusion of the investigated groups. 351 probands' families were studied: 57 with type II and 27 with type III gastric ulcer disease and 267 with duodenal ulcer disease. Gastric ulcer types were determined according to the classification of H. Johnson. The coefficient of genetic proportion in the cases of duodenal ulcer disease was additionally calculated according to the type of patients' familial pre-disposition. The coefficient of genetic proportion was found to acquire identical values for all groups studied without exception when calculated on the basis of one proband in a family (y = 1) both by the method of probands and the method of simple registration. The segregation coefficient values obtained using the direct methods of Weinberg do not support the hypothesis of monogenic transmission pattern either of the ulcer disease as a whole or of its different varieties.