GLA and Fabry disease: Fabry disease (FD) is a lysosomal storage disorder caused by mutations of the α-galactosidase A gene (GLA) on the X chromosome, determining enzymatic deficiency and subsequent pathological deposition of globotriaosylceramide (Gb3) and its deacylated form globotriaosylsphingosine (lyso-Gb3) in cells of various tissues.