The quantitative analysis of polymorphism on human chromosomes 1,9,16, and Y. IV. Heterogeneity of a normal population.

The generalized characteristic of the C-segment lengths on chromosomes 1, 9, 16, and Y is suggested for a study of population heterogeneity. For this purpose, the concept of the distance D is introduced, taking into account the individual C-segment lengths, the mean lengths and standard deviations of C-segment lengths in a group of subjects, as well as the coefficients of correlation of the C-segment lengths on the said chromosomes. It is demonstrated that distance D may be employed to study the relevance of the given subject to the group studied, the relation to the mean characteristics within the group, and selection of subjects' pairs with almost identical C-segment lengths on respective chromosomes. In the study of such problems as zygosity of twins, family analysis, etc., along with the absolute C-segment lengths, it is recommended to employ the relative C-segment lengths on chromosomes 1, 9, 16, and Y, calculated as a part of the sum total of their absolute lengths.