When I started on this journey to knowledge, decades ago I came across CblC disease. However, the high rate of infant death and statements like “… three known adult survivors” made it extremely unlikely that it could apply to me, or even any of us posting here at all. I commented to Rich that I doubt I had it since it so rare and so fatal and I shared all those symptoms in common with folks here. I also mentioned that for me to have CblC disease it would have to be rarely diagnosed instead of rare. @nandixon recently posted links to several recent articles talking about late onset (post infant) and adult onset CblC disease that is triggered by something. And guess what, it comes in so many variations they haven’t figured that out yet and the real incidence keeps climbing every time they add a new gene sequence to the polymorphisms. The disease is “extremely heterogeneous”, it varies widely and they don’t know what it looks like. It also responds poorly or not at all to HyCbl, folic acid and carnitine (ALCAR is usual when unspecified) which, it is agreed, is the best they know how to treat it currently, and it works poorly at best. However, I can’t help but notice that they (the researchers) choose, yet again, the worst possible forms of everything that “ought” to work based on what they know. Fortunately I found the versions that work, AdoCbl, MeCbl, Metafolin (l-methylfolate) and L carnitine fumarate (90%) OR ALCAR (10%) dependent up the person, not to mention potassium and all the rest that are needed and how individual the balance is. It’s caused by partial methylation block, methyltrap and partial ATP block, so familiar to us all. I am working on a lot more including lists of diagnoses included.