The aim of the present research work is to study the bilateral differences in the frequency of pattern types of homologous fingers in left-handed and right-handed individuals of both sexes. The sample comprised 379 healthy people, of Bulgarian ethnicity, aged 17-58 years. In the female group, there were 219 right-handers and 53 left-handers, while in males - 66 right-handers and 41 left-handers. Fingerprints were taken by the typographic method, in a rotating manner. Papillary patterns were classified into four main types. The data were statistically analyzed. The results showed significant bilateral differences in women (lefthanded and right-handed) in the frequency of ulnar loops of the third finger. In men righthanders, there were significant differences in the frequency of circular patterns of the first and fourth fingers. There were not any differences found in the bilateral comparison of the frequencies of pattern types in the left-handed men.
