Developmental Implications of Palmar Dermatoglyphics Among Highland and Lowland Peruvian Quechua

This study presents a comparison of quantitative palmar dermatoglyphic characters among highland and lowland Peruvian Quechua. These data are interpreted in light of an environmental hypothesis suggesting that hypoxia at high altitude affects the development of the fetus during the first trimester of gestation when dermal ridges are formed.

The highland population is from the village of Ondores in the Province and Department of Junin, and the lowland population, the only known Quechua-speakers from the tropics east of the Andes, is from the village of Pamashto in the Province of Lamas and the Department of San Martin. Historical accounts and anthropological studies attest to the close genetic affiliation of the two groups.

Predicated on the idea that hypoxia influences the rate of development of mitotically active tissues (e.g., dermatoglyphics), comparative analyses were performed on the following variables: the interdigital ridge-counts, asymmetry of ridge-counts, a-b ridge breadth, and the maximal atd angle. The interdigital ridge-counts were examined by canonical variate analysis, principal components analysis, and a multivariate analysis of variance on the principal component scores. Asymmetry was examined by tests on the means (directional asymmetry) and tests on the variances (fluctuating asymmetry). Comparative analyses of a-b ridge breadth and the maximal atd angle utilized analysis of covariance.

The multivariate analyses of the interdigital ridgecounts revealed significant highland-lowland differences. Comparison of mean asymmetry showed significant intergroup variation among males but not females. Tests on the variance of asymmetry were not significant for either sex. The analysis of covariance of a-b ridge breadth was not significant. The same was true for the atd angle, although the highland-lowland comparison of adjusted means approached significance at p = 0.05.

It is concluded that the significant comparative results for the palmar dermatoglyphics among these highland and lowland Peruvian Quechua groups may be considered possible supportive evidence for hypoxic effects on intrauterine development early in gestation.