Study of fingerprints in Argentina population for application in personal identification

- The minutiae analyzed present significant differences in their frequency of appearance.
- Each of the types of minutiae has different discriminatory value in the process of identification.
- These frequencies show differences intra-fingers, inter-fingers and sex.
- The results show significant differences for the frequency of the types of minutiae between study populations.

The fingerprints of the Buenos Aires and Chubut provinces in Argentina have been studied, with the aim of knowing and quantifying the variability of these features, which are used in the identification process. The data studied for this research was obtained from 330 individuals, of both sexes, from two Argentinian population samples (170 individuals from Buenos Aires and 160 from Chubut), which amounts to a total of 3300 fingerprints. The different types of minutiae were located, identified, and visually quantified in four areas on the fingerprint. Two perpendicular axes were drawn whose intersection was located in the center of fingerprint. In addition, a circle was defined on these quadrants whose radius cut fifteen ridges. This method divides the fingerprints into four quadrants with two sectors apiece. The results obtained for both populations were compared statistically with those published previously for an Argentinian population sample, which had been collected using the same methodology. Therefore, Argentina becomes the country with the most information in this matter.For both populations, the highest frequencies were of ridge endings, followed by bifurcations and convergences. In this study of minutiae, statistically significant differences were found between the area of the fingerprint (inside and outside the circle), males and females, and types of main pattern for both samples. However, although the results show common patterns in the distribution of minutiae, there are also significant differences between populations. This reveals a significant ancestral and frequency effect of the minutiae, which would indicate that the minutiae are more genetically dependent than has been suspected so far. Furthermore, the non-equiprobability found for the frequency of the types of minutiae indicates that the weight provided by these characteristics is not the same when applied in identification processes, whether used quantitatively (numerical standard) or qualitatively (holistic method).