I think that 60% figure is very misleading. While many have mutations, few have any visible effects from it. One initial test for it is if you have high homocysteine levels. The problem isn't always folate, though, it's can also be B12 or just B12. Homocysteine is controlled by having the right balance of folate, B6, and B12, not just folate. High homocysteine is thought to be a risk factor for heart disease. If you have too much of any one of these, it can alter the balance of the others, so it's possible that working on just folate might end up with higher homocysteine levels, not lower, as it might adversely affect B12 and B6. So you have to look at these three nutrients in concert kind of like you have to do with the electrolytes. A lot of this is being pushed by one popular naturopath on the internet, but docs don't believe the mutations actually affect very many people. You would know you were one of them in one way by not having a lot of energy, as the effect, as I understand it, is mostly on the methylation process of these vitamins, which is a process the body engages in to produce energy to fuel our cells. So you might well pursue this by doing some homework but if your methyl folate and methyl B12 are checking out okay docs aren't going to diagnose it as a problem. It's always your choice if you want to experiment, of course, but be alert to the interconnection between these three nutrients. I hope it goes well.