Interracial differences also exist concerning the melanocytic system. Even if each type of skin basically has the same number of melanocytes per unit of surface, there is no similarity concerning their structure (31) and their functionality (38). Whereas the melanosomes are small and concentrated in the keratinocytes to be then degraded in the superficial layers of the epidermis of Caucasian skins, they are much bigger, widely scattered in all the layers of the keratinocytes and are not degraded when they arrive in the horny layer of black skins, giving them a characteristic color (40). Colorimetric and spectrophotometric studies have shown that the interindividual and intersexual differences of skin coloration in the different races are mainly related to the blood concentration in hemoglobin for the Caucasian subject, both to the hemoglobin and melatonic pigment content in the Asian subject, and only to the concentration in melanin in the black subject (41).