PGM1-CDG is cause by pathogenic variants in PGM1. Missense, non-sense, frameshift splicing and gross rearrangement type variants were all reported. Genetic testing is the standard method to confirm PGM1-CDG diagnosis. Other complementary methods include PGM1 enzymatic measurements in leukocytes. PGM1 enzymatic testing cannot be performed in red-blood cells due to the absence of PGM1 in this cell type. Recently, suspected pathomechanism behind PGM1-CDG has been reported. PGM1 deficiency results in a depletion of Galactose-1-P, UDP-Glucose and UDP-Galactose. The latter are essential building blocks of glycosylation and therefore, PGM1 deficiency causes glycosylation abnormalities. In addition, D-Gal supplementation in PGM1-CDG results in an increase of these metabolites and therefore is able to restart glycosylation.
PGM1