Yoshiura K, Kinoshita A, Ishida T, Ninokata A, Ishikawa T, Kaname T, Bannai M, Tokunaga K, Sonoda S, Komaki R, Ihara M, Saenko VA, Alipov GK, Sekine I, Komatsu K, Takahashi H, Nakashima M, Sosonkina N, Mapendano CK, Ghadami M, Nomura M, Liang DS, Miwa N, Kim DK, Garidkhuu A, Natsume N, Ohta T, Tomita H, Kaneko A, Kikuchi M, Russomando G, Hirayama K, Ishibashi M, Takahashi A, Saitou N, Murray JC, Saito S, Nakamura Y, Niikawa N. A SNP in the ABCC11 gene is the determinant of human earwax type. Nat Genet. 2006 Mar;38(3):324-30.
Okay, firstly, that’s a lot of friggin’ authors. What’d they do, give everyone in the department credit? Anyway, there are apparently two types of earwax, wet and dry. East Asians frequently have dry earwax, while pretty much everyone else tends to have the wet variety. Earwax type is determined by a single little G->A SNP in a region of the ABCC11 gene, which encodes a transport protein that presumably determines the water content of earwax.
Miura K, Yoshiura K, Miura S, Shimada T, Yamasaki K, Yoshida A, Nakayama D, Shibata Y, Niikawa N, Masuzaki H. A strong association between human earwax-type and apocrine colostrum secretion from the mammary gland. Hum Genet. 2007 Jun;121(5):631-3.
There, that’s a more reasonable number of authors. If you are a woman, the type of earwax you have may be associated with the quantity of colostrum that you secrete. Colostrum is a particular type of milk produced by mammals in late pregnancy and a couple of days postpartum. It is nutrient-rich, low in fat, and chock full of immunoglobulins and growth factors (thanks, Wikipedia!).