That is awesome information Charlie1! I should’ve been more clear, though. Quest does offer MMA urine and blood testing. Yay! Although I went ahead and started on B-12 shots because I woke up the next day and my feet were tingling, I may still run all of the tests. That would be a serum B12, homocysteine, MMA and Holo-TC. I feel a video coming on! I scoped out various forums, and found a plethora of folks with high B-12 yet indicating B-12 deficiencies. It was enough to convince me that it was worth a try. So far, so good. My tingling has stopped in my hands and feet. Was it related to the B-12? We may never know. 🙂