Mild Left Ventricular Hypertrophy Unravels a Novel Nonsense Mutation of the GLA Gene Associated with the Classical Phenotype of Fabry Disease

We report on the clinical, biochemical, and genetic findings of a large family with the classical phenotype of Fabry disease due to the novel nonsense mutation c.607G>T (p.E203X) of the GLA gene, which occurs in the active site of the α-galactosidase A enzyme. This report highlights that (i) Fabry disease diagnosis should be considered in all cases of unexplained left ventricular hypertrophy (LVH), even in its milder forms; (ii) a complete evaluation of patients with unexplained LVH is important to find diagnostic red flags of treatable causes of LVH, such as Fabry disease; (iii) cascade family screening is paramount to the earlier diagnosis and treatment of other affected family members; and (iv) the Fabry disease phenotype is highly variable in heterozygote females, even within the same family.