PGM1 and vitamin B12-responsive methylmalonic acidemia: Some of the downregulated pathways in both the integrated TL proteomics and transcriptomics were, defective PMM2 causes PMM2-CDG (CDG-1a), defective MMAA causes methylmalonic aciduria type cblA, defective MUT causes methyl malonic aciduria mut type, glycogen storage disease types II, IV, XV and 0, defective PGM1 cause of PGM1-CDGII, MET activation of PI3K/AKT signaling, MET activation of PTPNII, inhibition of NO production, and stimulation of the cell death response by PAK-2P34 (labeled in red circles, Figure S4B and Table S2.1).