Inborn errors of vitamin B12 metabolism of the cblC class are caused by mutations in the MMACHC gene. Here, Guéant et al. report epi-cblC, a class of cblC in which patients are compound heterozygous for a genetic mutation and a secondary epimutation at the MMACHC locus.
- Jean-Louis Guéant
- Céline Chéry
- David S. Rosenblatt
