Discrimination of Down's syndrome with dermatoglyphic examination: An application of two dimensional graphic representation

Abstract

A method to discriminate Down's syndrome is proposed by the author by applying a two dimensional representation to the dermatoglyphic examination. For the parameters of this method, seven dermatoglyphic traits were selected, i.e. the type of hallucal pattern and the pattern type of index finger on both side, and the simian line, the maximal atd angle larger than 56° and the third interdigital patten on the right palm. These traits were transformed into a vector in order to illustrate an individual on a two dimensional plane. For each dermatoglyphic trait a certain length of weight was give and a certain angle was settled for each characteristic of the trait. Then, the coordinate point, the product of vectors derived from these traits, was plotted on the plane for individuals examined. The procedure is represented by the following formulas: {Mathematical expression} {Mathematical expression} This procedure was applied for dermatoglyphic data of 140 patients with Down's syndrome (131 cases of 21 trisomy, 7 cases of D/G translocation and 2 cases of G/G translocation) and 170 Japanese controls. The weighting length and angle which effectively discriminate both groups were determined empirically from the results of these materials (Fig. 1, Table 8). As shown in Fig. 3, the areas proper to the Down's syndrome and the controls were sharply separated except for one point where one patient and one control individual were encountered. Therefore, the dis- © 1978 Business Center for Academic Societies.