Rs17822931 : T or C

CC tend to have wet ear wax.

TT or CT tend to have dry ear wax. The T allele originated in Eastern Asia, and has spread throughout most of the world. Europeans that have dry earwax most likely got the dry ear wax allele from Asia sometime in their ancestry.

Futher reading:

This website has much more detail. It also explain how the gene for wet earwax also tends to give smelly armpits (apocrine sweat).

23andme has a nice summary of earwax genetics.