They also add new approaches to studying mild and severe TC I deficiency and to reducing confusion of its low cobalamin levels with those of cobalamin deficiency and its often dramatically different prognosis and management.
Although not significant when corrected for multiple testing, eight single nucleotide polymorphisms (SNPs) in two genes, transcobalamin II (TCN2) and the transcobalamin II-receptor (TCblR), were found to influence several clinical traits of cobalamin deficiency.
Complete absence of TC-II or total functional abnormality causes tissue vitamin B12 deficiency resulting in a severe disease with megaloblastic anemia and immunologic and intestinal abnormalities in the first months of life.
Putative binding sites for HCFC1 and its binding partner THAP11 were identified near genes of the glycine cleavage enzyme, providing a potential mechanistic link between HCFC1 mutations and increased glycine.