Polymorphism in Ear-Wax Types and its Anthropological Significance

It is well known that there is a very marked racial difference in the nature of cerumen or ear-wax. Caucasian and Negro peoples have generally brown, sticky and wet cerumen, while this type of cerumen is less common among Japanese where the majority has gray, brittle and dry cerumen. The distinction between these two types, wet and dry, is usually sharp and manifested soon after birth, so that diagnosis can easily be made by inspection of external ear canal if no pathologic complication is involved. It has been further noticed, even by layman, that there is an association between wet cerumen and axillary odor, the presence of which is deemed to be pathologic in Japan and is often considered to require medical treatment. Probably for this reason, there are a considerable number of Japanese literature which deal with the variation in cerumen, mostly in connection with axillary odor. Based on his own observations besides the results collected by other authors, the present author proposes to review the subject on the apparent polymorphism in ear-wax types from the view-point of genetics with special ref er ence to the anthropological significance of the finding on this trait.