Metacarpophalangeal pattern profiles in Venezuelan and northern Caucasoid samples compared.

Comparison of hand long-bone lengths and variances in published measurements of North American Caucasoid, Venezuelan, and English individuals, and of their metacarpophalangeal pattern profiles (MPP), revealed systematic differences between samples from infancy through adulthood. The variances of Venezuelan males tend to be larger than those of Americans, especially under 9 years of age. The same trend was observed for females, but to a lesser degree. The English sample showed variance similar to that of Venezuelans and Americans. Below 7 years of age, bones of Venezuelans were longer than those of Americans, except the distal phalanges, which always were longer in the latter, as were all bones after age 17. The index finger's middle and distal phalanges of Americans were relatively longer than the other bones at all ages. Females also showed this general trend, though not as clearly. Venezuelan adults had longer first and second metacarpals and proximal phalanges than the English adult homologs. American adults had all bones longer than those of English adults. The English adults showed a "typical" MPP, characterized by shorter proximal phalanges, both when compared with Venezuelan and with American adults. Genetic rather than environmental causes are likely as an explanation for these differences. This warned us against the indiscriminate use of any "standard" sample from a different population to establish objective profile patterns and sizes in abnormal cases, as illustrated with one example.