This is not unique for CDG; for example, it is a rather frequent finding in Phosphomannomutase deficiency.5 Interesting is the presence of proteinuria without other symptoms in some carriers.There is some phenotypic overlap with defects in other vacuolar H+‐ATPase subunits: cutis laxa in ATP6V0A2‐CDG, ATP6V1A, ATP6V1E1 and ATP6AP2; liver disease in ATP6AP2‐CDG, CCDC115‐CDG and TMEM199‐CDG; and immunodeficiency in ATP6AP2.6, 7, 8, 9, 10, 11 In males with sensorineural deafness, hair loss and proteinuria, screening for CDG should be performed. This evidence concerns the gene ATP6AP2 and immune system disorder.