The reciprocal influence of the different finger pattern types on their ridge count values

The mutual influence of fingertip pattern types, whorls (W), ulnar loops (Lu), radial loops (Lr) and arches (A), on the pattern ridge count (RC) values is evident from the dermatoglyphics of a sample of 606 Israeli Jewish males. The presence of W is associated with an increase in the RC of Lu and Lr of the same individual, and conversely, the presence of Lu, Lr or A coincides with a decrease in the RC of W. The presence of A decreases also the RC of Lu and Lr, but the reciprocal influence does not occur because the RC of A is, by definition, always equal to zero. When two different pattern types concomitantly affect a third type, the net results is an intermediate one. The modifying influence of a pattern on the RC of others is proportional to the number of fingers carrying that pattern. When the total RC of an individual is used for genetic or medical purposes, the reciprocal influences of fingertip patterns on pattern RC values must be considered.