ATP6AP1 and sensorineural hearing loss disorder: In patients with MPI-CDG, the clinical and biochemical phenotype was mainly expressed in the liver, whereas in other cases, liver involvement was associated with neurological manifestation/neurovisceral disease (PMM2-CDG, SRD5A3-CDG, ALG13-CDG, ALG1-CDG, ALG3-CDG, DPAGT1-CDG, NGLY1-CDDG), cardiac involvement (dilated cardiomyopathy and progressive cardiac insufficiency in the patient with PGM1-CDG), cutis laxa in ATPV0A2-CDG, sensorineural hearing loss, glomerular and tubular dysfunction in ATP6AP1-CDG.