... convert 6-pyruvoyltetrahydropterin to BH4 [64-66], which is an essential cofactor for tyrosinehydroxylase (TH) and tryptophan hydroxylase (TPH),both of which are involved in dopamine and serotoninbiosynthesis ... anintermediate, 6-pyruvoyl-tetrahydropterin (PPH4), to 1’-OXPH4, or 2’-OXPH4, and catalyzes the final step of tetrahydrobiopterin (BH4) synthesis, anessential cofactor for phenylalanine hydroxylase, tyrosine ... twin-family study of alcoholism in women. Am J Psychiatry 1994, 151:707-715.3. Pickens RW, Svikis DS, McGue M, Lykken DT, Heston LL, Clayton PJ:Heterogeneity in the inheritance of alcoholism. A study...