A comparative study of topological and sex differences in fingerprint ridge density in Argentinian and Spanish population samples

Althoughseveralstudieshave recentlyassessedsex differencesin fingerprintridge densityanditsvariability in human populations from different origins, such a study has not been carried out yet in the Amerindian population.Thegoalofthisstudywastodeterminethetopologicalandsexualdifferencesin fingerprintridge density (RD) in native subjects from two samples of northwestern Argentina (Jujuy province) living at differentaltitudes.TheresultswerecomparedwiththoseobtainedfromaSpanishpopulationsample.Thestudy was based on data from all 10 fingerprints of 393 adult Argentinian men and women, 193 from the PunaQuebrada region (more than 2500 m above sea level) and 200 from Ramal (500 m above sea level). Ridge density was assessed for three different areas (radial, ulnar and proximal) for all 10 fingers of each subject.In bothsamples,significantdifferencesbetweenareaswereobtained,soradialRD>ulnarRD>proximalRD.No significant differences were foundbetween samples in males, while femalesfrom both samples significantly differed in the radial and proximal areas. Females have higher RD, so narrower ridges, than men, in all areas andall fingers.ApplicationofBayes’theoremallowedustoobtainaridgedensitythresholdfordiscrimination ofsexesinArgentiniansamplesandthethresholdfordiscriminationofpopulationsbetweenArgentinianand Spanish samples. These results can be useful for forensic use.