ATP6AP1‐CDG: Follow‐up and female phenotype

In 2016, 11 male patients were reported with immunodeficiency and hepatic, gastric and (in some) neurological disease due to X‐linked ATP6AP1 deficiency (ATP6AP1‐CDG). In 2018, three other patients were reported with additional features: connective tissue abnormalities, sensorineural hearing loss, hyperopia, glomerular and tubular dysfunction, exocrine pancreatic insufficiency and altered amino acid and lipid metabolism. We here present a follow‐up of three reported siblings showing progression of deafness to total hearing loss, progressive loss of hair up to alopecia, chestnut skin and, at last follow‐up, in some of them proteinuria. Three female carriers showed a normal serum transferrin isoelectrofocusing but in two of them there was a persistent proteinuria.