D313Y variant in two related end-stage renal disease patients - Pathogenic or not yet?

Fabry disease is a multisystem lysosomal storage disorder caused by mutations in the GLA gene that result in a deficient or absent activity of alpha-galactosidase A. There is a wide spectrum of GLA gene variants, some of which are described as non-pathogenic. The clinical importance of the D313Y variant is still under debate, although in recent years it has been considered as a variant of unknown significance or a benign variant. Despite this prevailing notion, there are multiple case reports of patients with D313Y variant that presented signs and symptoms consistent with FD without any other etiological explanation. In this article, we present two family members with an important renal phenotype and other typical manifestations of FD (white matter lesions and left ventricular hypertrophy) that only had the D313Y variant. These cases suggest that this variant of unknown significance may contribute to the development of common features of FD and should not be undervalued.