TY - JOUR T1 - Splicing mutations in glycogen-storage disease type II: evaluation of the full spectrum of mutations and their relation to patients' phenotypes. JF - Eur J Hum Genet Y1 - 2011 A1 - Zampieri, Stefania A1 - Buratti, Emanuele A1 - Dominissini, Silvia A1 - Montalvo, Anna Lisa A1 - Pittis, Maria Gabriela A1 - Bembi, Bruno A1 - Dardis, Andrea KW - alpha-Glucosidases KW - Cell Line KW - Computational Biology KW - DNA Mutational Analysis KW - Exons KW - Glycogen Storage Disease Type II KW - Humans KW - Introns KW - Mutagenesis, Site-Directed KW - Mutation KW - Phenotype KW - RNA Splicing AB -

Glycogen-storage disease type II is an autosomal recessive-inherited disorder due to the deficiency of acid α-glucosidase. A large number of mutations in the acid α-glucosidase gene have been described to date. Among them, ~15% are variations that may affect mRNA splicing process. In this study, we have for the first time comprehensively reviewed the available information on splicing mutations of the acid α-glucosidase gene and we have evaluated their possible impact on the splicing process using different in silico approaches. Out of the 39 different GAA-sequence variations described, an in silico analysis using seven different programs showed that 97% of them are predicted to have an impact on the splicing process. Moreover, this analysis showed a quite good correlation between the impact of the mutation on the splicing process and the clinical phenotype. In addition, we have performed the functional characterization of three novel sequence variants found in Italian patients and still uncharacterized. Using a minigene system, we have confirmed their pathogenic nature. In conclusion, this study has shown that in silico analysis represents a useful tool to select mutations that affect the splicing process of the acid α-glucosidase gene and provides an updated picture of all this kind of mutations reported till now.

VL - 19 IS - 4 U1 - http://www.ncbi.nlm.nih.gov/pubmed/21179066?dopt=Abstract ER - TY - JOUR T1 - Long-term observational, non-randomized study of enzyme replacement therapy in late-onset glycogenosis type II. JF - J Inherit Metab Dis Y1 - 2010 A1 - Bembi, Bruno A1 - Pisa, Federica Edith A1 - Confalonieri, Marco A1 - Ciana, Giovanni A1 - Fiumara, Agata A1 - Parini, Rossella A1 - Rigoldi, Miriam A1 - Moglia, Arrigo A1 - Costa, Alfredo A1 - Carlucci, Annalisa A1 - Danesino, Cesare A1 - Pittis, Maria Gabriela A1 - Dardis, Andrea A1 - Ravaglia, Sabrina KW - Adolescent KW - Adult KW - Age of Onset KW - Aged KW - alpha-Glucosidases KW - Child KW - Enzyme Replacement Therapy KW - Female KW - Follow-Up Studies KW - Glycogen Storage Disease Type II KW - Humans KW - Male KW - Middle Aged KW - Observation KW - Time Factors KW - Treatment Outcome KW - Young Adult AB -

OBJECTIVES: Type II glycogenosis (GSDII) is a lysosomal storage disorder due to acid alpha-glucosidase (GAA) deficiency. Enzyme replacement therapy (ERT) with human recombinant alpha-glucosidase (rhGAA) has been demonstrated to be effective in the treatment of infantile forms of GSDII, but little information is available concerning late-onset phenotypes. Long-term follow-up studies are not available at present. The aim of this study was to evaluate the ERT long-term effects in late-onset GSDII.

METHODS: Twenty-four patients, including 7 juveniles and 17 adults, received bi-weekly infusion of rhGAA (20 mg/kg) for at least 36 months. Clinical conditions, muscular function (6-min walking test, 6MWT; Walton scale, WS), respiratory function (vital capacity, VC; forced expiratory volume, FEV1; arterial pCO(2)), and muscle enzymes were assessed every 6 months.

RESULTS: The 6MWT improved in both juvenile and adult patients (p = 0.01, p = 0.0002, respectively), as well as in patients with moderate to severe muscle function impairment (WS >3.5; p = 0.002). An overall improvement in WS was also observed (p = 0.0003). VC and FEV1 remained unchanged, while pCO(2) decreased (p = 0.017). Muscle enzymes decreased significantly (p < 0.0001). Two patients (8%) showed transient secondary events during ERT.

CONCLUSIONS: Long-term ERT with rhGAA was shown to be safe, well tolerated, and effective in improving motor function and in stabilizing respiratory function in late-onset GSDII. The response pattern showed a progressive clinical improvement during the follow-up period in juvenile patients, while in adults it reached and maintained a plateau after the first year of treatment.

VL - 33 IS - 6 U1 - http://www.ncbi.nlm.nih.gov/pubmed/20838899?dopt=Abstract ER -