Could anyone give me some guidance on supplementation for B12? I am double homozygous Met/Met for COMT V158M and H62H. I am heterozygous for VDR Bsm and VDR Taq, which I understand are also related to dopamine. The only MTHFR mutation I have is A1298C, which as I understand it, does not affect homocysteine. Okay, here's my problem: When I supplement with methylcobalamin I become very tired (too much dopamine?) and when I supplement with hydroxycobalamin as suggested for COMT Met/Met ++, I feel wired. In the meantime my B12 has now gone down to 163 because I am reluctant to use either form, and I need to do something about it. Any guidance, experience, suggestions, thoughts? Thanks so much.