PROTOCOL TO EVALUATE GAA ACTIVITY & GENE MUTATIONS IN LATE-ONSET POMPE DISEASE

这个子项目是众多研究子项目之一

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Pompe disease is rare autosomal recessive metabolic muscle disease caused by a deficiency or lack of acid alpha glycosidase (GAA), a critical enzyme used to degrade lysosomal glycogen. In Pompe disease, an excessive amount of glycogen builds up in various tissues, especially skeletal muscle that prevents their normal function. Genzyme Corporation has manufactured a recombinant form of human acid alpha-glucosidase, (rhGAA), Myozyme, an investigational enzyme replacement therapy (ERT) for Pompe disease. It is hoped that ERT will restore lysosomal GAA activity, deplete accumulated lysosomal glycogen, and prevent further substrate accumulation. rhGaa is produced from Chinese hamster ovary cells into which the complementary deoxyribonucleic acid (cDNA) coding for GAA has been stably expressed. Clinical trials for infantile onset form are currently closed to enrollment. Presently newly diagnosed infantile onset patients may receive ERT under an expanded access program initiated by Genzyme. The late-onset Prospective Observational Study (LOPOS) began in 2004 and is fully enrolled with 58 individuals with mild to intermediate late-onset Pompe Disease. Clinical trials must begin for adult patients coping with late-onset Pompe disease. This protocol will screen potential patients for participation in these clinical trials. Hypothesis: This screening protocol is designed to evaluate potential candidates for future Myozyme clinical trials and identify suitable participants.