Has anyone heard of the MTHFR gene? I was tested and have this gene. Basically this means that my body does not metabolize B Vitamins well. B vitamins are critical for nerve and brain health. I use methylized B Vitamins and it has really been a game changer for my numbness and tingling in my legs. The MTHFR test is offered several companies. Seeking Health and Life Extension are two companies that I know offer this test. Millions of people carry this gene.