[Medical genetic study of the population of Turkmenia. VI. An analysis of the genetic component of fertility dispersion in the population of Nokhor].

The index of the total opportunity for selection (the Crow index) and the genetic part of total variance in progeny size was studied in small Turkmenian isolated population "Nochur". The average number of children per family in families that had completed their reproductive period was 6.84, the variance being 12.31. The index of total opportunity for selection was computed by the standard method of J. Crow: Jm = 0.313, Jf = 0.454, Jtot = 0.909. Some correlation coefficients of the progeny size were calculated. The sister-sister correlation coefficient was significantly distinguished from 0 and was equal to +0.22. Thus, the genetic part of total variance of the progeny size is 0.4-0.5. It is essential for understanding of the Jf estimation.