In particular, NS in infancy or early childhood has been observed in some subtypes of CDG, such as PMM2-CDG (phosphomannomutase 2-congenital disorder of glycosylation) and ALG1-CDG (ALG1-congenital disorder of glycosylation) [126,128,136,137]. Here, ALG1 is linked to congenital disorder of glycosylation.