[Hand dermatoglyphics in patients with isolated triphalangia and Holt-Oram syndrome].

A comparative analysis of dermatoglyphic prints of patients with the Holt-Oram syndrome and isolated triphalangeal thumbs was performed with control dermatoglyphics. A specific feature of the syndrome is a change in the main palmar lines and their termination on the radial border of the hand not only in the absence of the thumb but also in the case of formation of the abortive xT-line, its radiants, and the axial triradius. This trait may be considered diagnostic for the Holt-Oram syndrome. Cases of triphalangeal thumbs with preaxial polydactyly do not reveal significant changes in dermatoglyphic patterns and appear to result from partial duplication of the thumb. An isolated triphalangeal thumb may be the result of an atavistic development of homeotic transformation of the thumb.