There are two distinct genetically determined types of earwax: the wet type, which is dominant, and the dry type, which is recessive. East Asians and Native Americans are more likely to have the dry type of cerumen (grey and flaky), whereas Caucasians and Africans are more likely to have the wet type (honey-brown to dark-brown and moist).[6] Cerumen type has been used by anthropologists to track human migratory patterns, such as those of the Inuit.[7] The consistency of wet type earwax is due to the higher concentration of lipid and pigment granules (50% lipid) in the substance than the dry type (30% lipid).[3]
http://en.wikipedia.org/wiki/Earwax