Regression analysis of digital ridge counts on pattern intensity index: a developmental interpretation.

Regression analyses of digital ridge counts on pattern intensity index (PII) are performed on data from three populations. The results for two Papua New Guinean populations (608 subjects from Karkar Island and 397 from Lufa sub District) are compared with those for a dermatoglyphically very different population from the Faroe Islands (296 subjects). Digital relationships are examined within each population. Equating the statistical regression of digital ridge counts with the embryological regression of apical volar pads, some biological interpretations of the findings are suggested. The results indicate that developmental fields across the embryological hand interact with genotype to produce digital differences in dermatoglyphic phenotype.