Sexual dimorphism in the Chuvashian population of Russia in two types of dermatoglyphic traits: principal component analysis

With the aim of determining sexual dimorphism in the component structures among the Chuvashian population of Russia, finger and palmar dermatoglyphics of 547 individuals (293 males, 254 females) were analyzed. The sex differences in two categories of dermatoglyphic traits (22 quantitative traits and 38 asymmetry and diversity traits) are reflected differently and contradictory with other ethnic groups. However, a common feature of the factor 1 "digital pattern size factor" (finger ridge counts from the first category of traits) indicate its degree of universality when compared with other populations, which suggests that the variability of finger ridge counts is determined by the same genes that control the pattern types. The factors "intra-individual finger diversity factor", and "bi-lateral asymmetry factor" extracted from the second category of dermatoglyphic traits are also similar in both sexes. However, these components are hardly described in the literature. The nature of variation of these components (from two categories of dermatoglyphic traits) appears with a good similarity between sexes, which suggests their common biological validity of the underlying component structures of the finger and palmar dermatoglyphic characters.