The purpose of this first “Round-table Conference” could well be to present the historical development of human genetics from the early days of Mendelism to the elaboration of modern genetic research. The refinement of methodological possibilities and the unfolding of problems indicate to us the proper lines for further study. With this introduction I should like to restrict myself to a few remarks concerning the role of the gene analytical system of Gregor Mendel in human genetics. If as a result of corrent research the concept of the gene has undergone important alterations and is no longer the closed unit of the classical formulation, it still remains a useful concept for practical research. Every investigation of a genetically active factor immediately begins with the determination of a segregating unit or a mutating unit. Determining an allele relationship or a series of multiple alleles will remain the principal result. Quite often in human genetics it has not been possible to demonstrate these relationships as pseudoallelal or with other methods to achieve a differentiation of the gene concept into its subunits: the cistron, recon and muton. So far the objectives of human genetics the employment of the gene concept as classically formulated is methodologically necessary.

The ideal goal of the gene analytical method is to determine the function of all genes which take part in the heredity of an organism, the preparation of theoretical chromosome maps for the various linkage groups, the determination of the relationships between the genes and their alleles to visible or measurable characteristics of the organism, and the establishment of relationships between phenotypic expression and dominance or epistasis. Its further area of interest is in the genetic analysis of natural populations, the question of spontaneous mutability, the problem of genetic diversity and the polymorphism caused by it in populations, and the equilibrium between all alleles. These questions lead necessarily to general problems of population dynamics, adaptation and evolution.