Genes that associate with serum B12 and folate levels are in pathways affecting their metabolism.
Genes previously identified to harbor variants regulating serum levels of B12 are shown in green. In blue are novel genes identified in the present study. In red, genes containing variants previously suggested to associate with serum folate and in purple are novel genes for serum folate. B12: vitamin B12; HC: Heptocorrin (TCN1); IF: Intrinsic factor; R-A-P: Receptor-Associated-Protein; CUBN: cubilin (intrinsic factor-cobalamin receptor); TCII: Transcobalamin II (TCN2); TCII-R: Transcobalamin II receptor (CD320); MMACHC: methylmalonic aciduria (cobalamin deficiency) cblC type, with homocystinuria; MMAA: methylmalonic aciduria (cobalamin deficiency) cblA type; ABDC4: ATP-binding cassette, sub-family D (ALD), member 4; LMBD1: LMBR1 domain containing 1; FOLR1–3: folate receptors 1–3; Ado-B12: Adenosyl-cobalamin; Me-B12: Methyl-cobalamin; Me-mal-CoA: Methyl-malonyl-CoenzymeA; Suc-CoA: Succinyl-CoenzymeA; MUT: methylmalonyl-CoA mutase; H. pylori: Helicobacter pylori; DHFR: Dihydrofolate reductase; MS: methionin synthase; THF: Tetrahydrofolate; 5,10-MTHF: 5,10-Methyl-tetrahydrofolate; Hcy: Homocysteine MTHFR: 5-methyl-tetrahydrafolate reductase.