title: [Severe form of juvenile type II glycogenosis in a compound-heterozygous boy (Tyr-292--> Cys/Arg-854-->Stop)].
abstract: BACKGROUND
  Type II glycogenosis is a glycogen storage disease inherited as an autosomal recessive trait. This molecular and clinically heterogeneous condition is due to a deficiency in a lysosomal acid 1,4-alpha-glucosidase.
  
  
  OBJECTIVE
  To report the clinical, enzymatic and molecular characterization of a mulatto child, born to healthy Dominican mother and Caucasian father, affected by the juvenile phenotype form of type II glycogenosis.
  
  
  METHODS
  This 16-month-old male presented from 10 months with motor delay, limb-girdle hypotonia, prominence of calves, increased CPK value, mixed myotonic/myopathic pattern on EMG, intense glycogen muscle storage (775 micrograms/mg of protein) and severe deficiency of 1,4-alpha-glucosidase activity (< 0.03 mU/mg of protein). At 24 months he developed a rapidly progressive hypotonia and respiratory failure. The patient was found to be compound heretozygote for the novel mutation Tyr-292-->Cys, coming from the father, and Arg-854-->Stop, coming from the mother and previously reported in two Afroamerican patients, one with the adult phenotype and the other with the juvenile one.
  
  
  CONCLUSIONS
  The present case corresponds to a severe form of type II juvenile glycogenosis. The severity of this condition may be related to the observed mutations and the associated extremely low muscle enzymatic activity.
authors.affiliation: Departamento de Pediatria, Hospital General de Galicia, Santiago de Compostela, España. pdcastro@uscmail.usc.es
authors.forename: M
authors.initials: M
authors.lastname: Castro-Gago
authors.forename: J
authors.initials: J
authors.lastname: Eirís-Puñal
authors.forename: A
authors.initials: A
authors.lastname: Rodríguez-Núñez
authors.forename: E
authors.initials: E
authors.lastname: Pintos-Martínez
authors.forename: T
authors.initials: T
authors.lastname: Benlloch-Marín
authors.forename: F
authors.initials: F
authors.lastname: Barros-Angueira
mesh_terms: D003062:Codon / Q000235:genetics; D018388:Codon, Terminator; D018450:Disease Progression; D005087:Glucan 1,4-alpha-Glucosidase / Q000172:deficiency / Q000235:genetics*; D006009:Glycogen Storage Disease Type II / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D006579:Heterozygote; D006801:Humans; D007223:Infant; D008297:Male; D009124:Muscle Proteins / Q000172:deficiency / Q000235:genetics; D018482:Muscle, Skeletal / Q000201:enzymology / Q000473:pathology; D010641:Phenotype; D017354:Point Mutation; D000520:alpha-Glucosidases
chemical_list: D003062:Codon; D018388:Codon, Terminator; D009124:Muscle Proteins; D000520:alpha-Glucosidases; D005087:Glucan 1,4-alpha-Glucosidase