Skin color. Could it be a new fingerprint?

OBJECTIVE To prove that the difference in human skin color can be used as a new fingerprint. METHODS A cross-sectional descriptive study was conducted in the Faculty of Medicine, The National Ribat University, Khartoum, Sudan between January and June 2010. The study consists of 139 subjects, which includes 41 Sudanese identical twins (82 subjects), 50 subjects from the general population, and 7 Chinese. All subjects were free of skin lesions. Based on reflectance spectrophotometry, the skin color has been read for all subjects from the inner upper arm using the Medisun skin check. Visual judgment on color differences was carried out directly with 3 normal observers, and through digital photos. RESULTS Skin color was found to be different in all subjects under the study depending on visual judgment, digital photos, and skin color readings. Differences in skin color were also found between different parts of the body (color map). Color intensity reading in the first twin was 4.010 +/- 0.5, and in the second twin was 3.89 +/- 0.44 with a significant difference (p=0.001). The general population sample showed significant differences in skin color from each other, and from the Chinese group (p=0.002). CONCLUSION In this study, we found that skin color between identical twins is different, as well as in the whole population, and could be a new personal identification method, which needs further international studies.