Clinical, histological and molecular characteristics of Mexican patients with Fabry disease and significant renal involvement.

Background And Aims: Fabry's disease (FD) is an X-linked lysosomal disorder caused by a deficiency of the enzyme α-galactosidase A that produces accumulation of glycosphingolipids with clinical abnormalities of skin, eye, kidney, heart, brain, and peripheral nervous system. We undertook this study to describe the molecular characteristics of the first four Mexican patients with diagnosis of FD with significant renal involvement, correlating these molecular characteristics with clinical, pathological and biochemical findings.

Methods: Genomic DNA from Mexican nonrelated patients with presumptive diagnosis of FD was sequenced by polymerase chain reaction (PCR). DNA sequences were compared against sequences in world data bank gene for alpha-galactosidase A (α-GLA, ENSG00000102393) using the BLAST database.

Results: Three patients were confirmed as having FD by displaying mutations in the α-GLA gene. The mutations found are a substitution (p.L243 F) in patient 1, and a substitution (p.A156 V) in patient 3. These two mutations had been previously reported. The new mutation was in patient 2 who displayed a deletion (c.260delA) changing the open reading frame from codon 86 and a stop codon at the 105th residue of the protein, (instead of 429 AA). The fourth patient had lack of mutations in any of the seven exons of α-GLA or 25 base-pair flanking regions; had mild manifestations with kidney histopathological diagnosis of FD that gave us a final diagnosis of atypical phenotype of FD.

Conclusions: Although the sample is small, it gives a first idea of the molecular and clinical heterogeneity of FD in a Mexican population.