Dermatoglyphic analysis of polydactylies in man: identification of digital morphogenetic fields.

We analyzed dermatoglyphic patterns of patients with pre- and postaxial polydactylies. It was found that (i) an additional finger was always accompanied by the respective digital triradius, radiants and the main line, and (ii) in postaxial polydactylies a circular pattern of epidermal ridges around the 6th finger and a 2nd additional triradius are formed. On this basis it is suggested that the palmar main lines, radiants and digital triradii serve as marker structures and borders in the process of differentiation of digital morphogenetic fields out of a unitary field organized in a fashion described by a polar coordinate system model.