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S Aurino

Publications and source records attributed to S Aurino.

4 recordsLinked to original sources

Early onset calpainopathy with normal non-functional calpain 3 level.

Limb girdle muscular dystrophy 2A (LGMD2A), caused by calpain 3 deficiency, is currently diagnosed through the immunodetection of muscle protein by Western blot (WB) analysis . However, WB may provide normal results in patients with LGMD2A. The case of a female (3y 6mo of age) is described. She was found to be affected by asymptomatic hypercreatine-kinaesaemia during routine biochemical analysis at 10 months of age and had developed myopathic signs at the last neurological assessment. The WB of muscle biopsy performed at 28 months of age showed a normal quantity and pattern of bands for calpain 3. Despite this finding, on molecular analysis she was found to be a compound heterozygote for two mutations of the calpain 3 (CAPN3) gene (R110X and G222R). Autocatalytic activity assay showed a loss of function of calpain 3. This is the first genetically confirmed case of very early onset calpainopathy with a normal amount of protein at WB. Molecular analysis is also suggested in very young patients with normal WB.

Blotting, Western↗

Readthrough strategies for stop codons in Duchenne muscular dystrophy.

Duchenne muscular dystrophy is due to mutations of the dystrophin gene. These are large deletions or duplications in 80% of cases, while premature stop codons (nonsense point mutations) account for 7% of cases. This subgroup of patients may take advantage of the properties of the antibiotic gentamicin to suppress stop codons (readthrough). The efficiency of the readthrough varies inversely to the efficiency of a stop codon and is also affected by the different components of the drug. Following gentamicin treatment of mdx mice, dystrophin was re-expressed up to 20% of normal level, albeit with variability among animals. Human trials with gentamicin have so far obtained doubtful results. PTC124 belongs to a new class of small molecules that mimics at lower concentrations the readthrough activity of gentamicin. The administration of PTC124 resulted in the production of full-length and functionally active dystrophin both in vitro and in mdx mice. A Phase II clinical trial is now in course and will be terminated at the end of 2006.

Aminoglycosides↗

Extensive scanning of the calpain-3 gene broadens the spectrum of LGMD2A phenotypes.

BACKGROUND: The limb girdle muscular dystrophies (LGMD) are a heterogeneous group of Mendelian disorders highlighted by weakness of the pelvic and shoulder girdle muscles. Seventeen autosomal loci have been so far identified and genetic tests are mandatory to distinguish among the forms. Mutations at the calpain 3 locus (CAPN3) cause LGMD type 2A. OBJECTIVE: To obtain unbiased information on the consequences of CAPN3 mutations. PATIENTS: 530 subjects with different grades of symptoms and 300 controls. METHODS: High throughput denaturing HPLC analysis of DNA pools. RESULTS: 141 LGMD2A cases were identified, carrying 82 different CAPN3 mutations (45 novel), along with 18 novel polymorphisms/variants. Females had a more favourable course than males. In 94% of the more severely affected patient group, the defect was also discovered in the second allele. This proves the sensitivity of the approach. CAPN3 mutations were found in 35.1% of classical LGMD phenotypes. Mutations were also found in 18.4% of atypical patients and in 12.6% of subjects with high serum creatine kinase levels. CONCLUSIONS: A non-invasive and cost-effective strategy, based on the high throughput denaturing HPLC analysis of DNA pools, was used to obtain unbiased information on the consequences of CAPN3 mutations in the largest genetic study ever undertaken. This broadens the spectrum of LGMD2A phenotypes and sets the carrier frequency at 1:103.

Adult↗

Beta-sarcoglycan gene mutations in Turkey.

The term limb-girdle muscular dystrophy (LGMD) refers to a group of muscular dystrophies that, at the outset, affect primarily the muscles of the hip and shoulder girdle. Limb-girdle muscular dystrophy is genetically heterogeneous comprising autosomal dominant (types LGMD 1A-1E) as well as autosomal recessive forms (types LGMD 2A-2J known). A subgroup among the autosomal recessive forms comprises the sarcoglycanopathies (LGMD2C-2F), caused by mutations in the gamma (gamma-SG), alpha (alpha-SG), beta (beta-SG) and delta (delta-SG) sarcoglycan genes, respectively. The sarcoglycans form the sarcoglycan complex, part of the dystrophin-associated glycoproteins. Mutations in the beta-SG gene causes LGMD2E. Disease severity, in this form, varies from mild to severe phenotypes depending on the individual mutation. Homozygous missense mutations in critical locations may result in the total absence of alpha-, beta- and gamma-sarcoglycan from the muscle membrane and a phenotype as severe as null mutations. In the present study, through screening 80 unrelated LGMD2 families, we identified 13 families with LGMD2E. Mutations in the beta-SG gene were identified in 12 patients from nine families. One of these patients carried a previously reported truncating mutation (Q11X), while the other 11 carried novel missense/rameshift mutations (M1L, V89M, I92T, I92S, 739insA), some of which were seen in more than one patient and may, therefore, be more common in the Turkish population.

Adolescent↗