PMM2 and liver disorder: Defects in mannose-6-phosphate isomerase (PMI, EC 5.3.1.8) cause MPI-CDG (Figure 3A), a disorder characterized by severe protein-losing enteropathy (Jaeken et al., 1998; Niehues et al., 1998), liver disease (de Koning et al., 1999), and coagulopathy resulting in recurrent thrombosis (Girard et al., 2020).