Fatigue, which is a feeling of extreme tiredness, weakness, or exhaustion, is the first symptom of almost every medical problem, including MTHFR. It can be linked to almost every body system, and it is the most general symptom we have. It is also linked to a number of common gene SNPs, including MTHFR, fast MAOA, fast COMT, and more. It is tied to lifestyle factors like diet, nutrition, sleep, and stress. So, actually, in light of all of that, it is surprising any of us don't