Fabry disease is an X-linked recessive inborn metabolic disorder caused by a deficiency of the lysosomal enzyme α-galactosidase A (EC 3.2. throughout the 7 exons of the α-galactosidase A gene (GLA). Mutation hotspots for Fabry disease do not exist. We examined 62 Fabry patients in Japan and found 24 GLA mutations, including 11 novel ones. A potential treatment reported for Fabry disease is active site specific chaperone (ASSC) therapy using 1-deoxygalactonojirimycin (DGJ), an inhibitor of α-galactosidase A, at subinhibitory concentrations. We transfected COS-7 cells with the 24 mutant GLAs and analyzed the α-galactosidase A activities. We then treated the transfected COS-7 cells with DGJ and analyzed its effect on the mutant enzyme activities. The activity of 11 missense mutants increased significantly with DGJ. Although ASSC therapy is useful only for misfolding mutants and therefore not applicable to all cases, it may be useful for treating many Japanese patients with Fabry disease. © 2007 Wiley-Liss, Inc.KEY WORDS: α-galactosidase A; GLA; lysosomal storage disease; 1-deoxygalactonojirimycin; chaperone therapy INTRODUCTIONFabry disease (FD; MIM# 301500) is a pan-ethnic, X-linked, lysosomal storage disorder caused by a deficiency in the lysosomal enzyme α-galactosidase A (EC 3.2.1.22) (Brady et al., 1967). Human α-galactosidase A is a homodimeric glycoprotein with three N-linked oligosaccharide chains on each subunit. Enzyme deficiency results in a systemic lysosomal accumulation of glycolipids, primarily globotriosylceramide (Gb3), in the vascular endothelium and other tissues. In the classical form of the disease, the patient develops angiokeratoma, hypohidrosis, and episodic pain crises in the extremities during childhood or adolescence. With advancing age, the morbidity of renal failure, cardiac disease, and early onset of stroke increases. The severity of the clinical manifestations depends on the amount of residual α-galactosidase A activity. Hemizygous male patients with no or very low α-galactosidase A activity usually have severe clinical symptoms and die as young adults. Heterozygous female Fabry patients exhibit a wide range of severity, from a virtually symptom-free course (Marguery et al., 1993) to one comparable to that of their male counterparts (Whybra et al., 2001), although they usually have no symptoms or very mild manifestations.We examined Fabry patients in Japan and sequenced the patients' α-galactosidase A gene (GLA) (MIM# 300644). To analyze the mutant α-galactosidase A activities, we transfected COS-7 cells with the mutant GLAs. In addition, since 1-deoxygalactonojirimycin (DGJ) stabilizes the α-galactosidase A conformation and improves its stability (Asano et al., 2000;Ishii et al., 2000;Yam et al., 2006), we added DGJ to the incubation medium and examined its effect on the mutant α-galactosidase A activities. MATERIALS AND METHODS PatientsWe examined 62 Fabry patients from 31 unrelated families. Diagnosis was based on reduced or absent α-galactosidase A activity and typical signs an...

Post-transcriptional gene-silencing methods (PTGS), including RNAi, are becoming increasingly pervasive in functional genomics. To advance analysis of the recently sequenced Coprinus cinereus genome, a high throughput gene silencing method is essential. We have exploited the GFP reporter gene to evaluate and quantify efficacy of three different silencing strategies. Modular constructs that encompassed antisense, untranslatable sense, and RNAi-mediating hairpin sequences, were transformed into a GFP-expressing host strain. Transformants exhibiting strong downregulation and partial suppression of GFP were recovered with all three constructs. Analyses of protein and transcriptional nucleic acids revealed that the antisense and hairpin sequences yielded similar levels of GFP suppression, and were both more efficient than untranslatable sense sequences. Our antisense vectors will expedite functional characterisation of C. cinereus and the modular nature of the constructs should permit exploitation of directional cDNA libraries for high throughput screening.

We describe two cases of Fabry disease in non-blood-related Japanese men, manifesting recurrent stroke even after the start of enzyme replacement therapy. Both exhibited chronic inflammation and ocular involvement with elevated levels of serum C reactive protein prior to the onset of stroke. We, therefore, suggest the association among persistent inflammation, ocular involvement and recurrent stroke in a certain subset of Fabry disease patients. Both cases received enzyme replacement therapy with no improvement in inflammatory signs or laboratory data. These cases suggest that Fabry disease should be considered in young patients with cryptogenic stroke or CNS manifestations and fever of unknown origin.

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