Human chromosomal polymorphism. VI. Chromosomal Q polymorphism in Turkmen of the Kara-Kum desert of Central Asia.

Chromosomal Q polymorphism was studied in 116 Turkmen, aboriginals of the Kara-Kum desert of Central Asia. Propylquinacrine mustard was used as fluorochrome. Of the 116 subjects aged 16-20 years, 109 (94.0%) were found to have Q-polymorphic variants, while seven (6.0%) showed complete absence of Q bands with fluorescence levels 4 and 5. There was a total of 351 polymorphic Q bands, 0-7 per individual, with a mean of 3.0 in the population. No differences between sexes were observed in the frequency of Q bands. The observed homo- and heteromorph frequencies proved to be in complete agreement with those predicted by the law of Hardy-Weinberg. Chromosome 3 with pericentric inversion of the Q-heterochromatin band was found in two (1.7%) of the 116 subjects. The following questions were examined: (1) the possible selective value of chromosomal Q-heterochromatin material in the adaptation of human populations to extreme environmental factors, in particular to the desert climate; (2) intraracial heterogeneity in Europoids of Eurasia; (3) the taxonomic value of Q polymorphism in ethnic anthropology.