The biggest assumption for differences in race's arises from the color of skin a person may have. This has been found to be an error by a research study published for the genetics of skin color in Africans. This research study has found eight genetics variants of the human genome that strongly influence pigmentation. Like other mammals, humans have melanosomes that are packed with pigment molecules (more pigment results in darker skin). In order to discover the genes that produce pigments, those with European ancestry were studied and a mutation called SLC24A5 was the cause for paler skin. African population on the other hand varies in skin color. From a study of 1570 people from African countries, a set of genetics variants accounted for 29% of variations in color were discovered. One variant MFSD12 affected skin color producing darker color. Dr. Tishkoff and her team have found that variants for dark skin were inherited from an African population and that variations for lighter skin were introduced by interbreeding with Neanderthals.