DPM2-CDG is caused by changes in DNA specifically responsible for DPM2 protein. DPM2 is a part of a larger protein complex -DPMS. DPMS is involved in many processes in the cell that help the cell function properly. Pathogenic changes in DPM2 result in a defective DPMS, whose function is disrupted. Therefore, DPM2 deficiency results in a disorder. Patients with DPM2-CDG specifically have a problem with glycosylation, a biochemical process that is responsible for production of glycans- sugar chains. These sugar chains are important as they are involved in many cellular processes and help maintain homeostasis.