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![]() ![]() ![]() ![]() ![]() ![]() ![]() First | Previous | Next | Last | | Index | Home Slide 101 of 109 To most people's surprise, there are no specific genes that define any particular race. In other words, all races share exactly the same genes. The races do exhibit polymorphisms (genetic variation at a specific locus), which tend to be more or less predominant in certain races, although nearly all can be found among all races in at least low levels. The major determinant of race, skin color, is controlled by genes that are present in all races. However, a recent study has shown that a single base pair change in the SLC24A5 gene resulted in the loss of pigmentation in Caucasian humans.1 Melanin, which exists in two forms (phenomelanin and eumelanin) is expressed as yellow and black skin color, respectively. The darkness of skin color (expression of melanin) is dependent upon the enzyme tyrosinase, which all races have in enough abundance to have very black skin color. However, the regulation of tyrosinase determines what color the skin appears. References
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Last Modified December 23, 2005