The present study examined the association of the Tyrosine hydroxylase Val-81-Met polymorphism with alcohol dependence. One hundred and fifty-nine patients in a psychiatric unit with alcohol dependence were genotyped as well as 92 healthy volunteers. The Val allele was more frequent in patients with alcohol dependence (69.5%) than in controls (62.5%). This effect was largely due to the association with early-onset alcoholism (77.8%), whereas no difference was noted between late-onset patients and controls. Our results suggest a role for tyrosine hydroxylase in early-onset alcoholism.