Interestingly, the two siblings described here showed a very similar clinical pattern, including very similar facial features, whereas siblings with other CDG disorders do not necessarily share as many clinical characteristics, for example, in ALG3‐CDG.16 The MPDU1‐CDG siblings shared the following abnormalities: massive dilatation of the intrahepatic biliary duct system, small renal cysts, buphthalmos with glaucoma, DCM, thrombocytopenia, elevated CK, and low ATIII. The gene discussed is SERPINC1; the disease is congenital disorder of glycosylation.