Single-digit fingerprint analysis for hand determination: A study of twinned loops.

In fingerprint analysis, the determination of hand (right or left) is one of the keys to resolving questions regarding the identity of the donor of the print. It is rare to encounter a complete set of 10-digit fingerprints from the scene of a crime. Although vital and imperative, except for a few studies on whorl patterns, the use of single-digit prints and patterns to ascertain the hand of the donor is scarcely reported in the literature. This research describes a novel approach whereby an analysis of twinned loops was carried out to identify the various parameters that may be helpful in ascertaining the hand of the donor. Bilateral rolled fingerprints from 180 healthy consenting adults belonging to a heterogeneous population of central India were collected. Out of the total of 1800 prints taken, 100 twinned loops (50 on the right hand and 50 on the left hand) were analysed. The following six parameters were considered: the slope of the flow of the apex ridges, the distance between the left delta and the ascending core, the distance between the right delta and the ascending core, mid-core position, the position of the loop and ridge tracing. On applying the chi-square test, the results were found to be statistically significant. Therefore, these parameters were found suitable for the determination of the hand from a single twinned-loop print.