a method of studying hereditary traits based on the analysis of pedigrees. This method allows us to determine how different characteristics are passed on from generation to generation and to assess the likelihood of certain traits appearing in future offspring. The use of this method is possible in the case when direct relatives are known – the ancestors of the hereditary trait (proband) on the maternal and paternal lines in a number of generations or the descendants of the proband in at least 3 generations.