Leaky splicing mutation in the acid maltase gene is associated with delayed onset of glycogenosis type II.

摘要: An autosomal recessive deficiency of acid {alpha}-glucosidase (GAA), type II glycogenosis, is genetically and clinically heterogeneous. The discovery an enzyme-inactivating genomic deletion exon 18 in three unrelated genetic compound patients - two infants adult provided a rare opportunity to analyze the effect second mutation who displayed dramatically different phenotypes. A Lys-903 one patient substitution Arg for Leu-299 another resulted fatal infantile form. In adult, T-to-G base change at position-13 intron 1 alternatively spliced transcripts with 2, location start codon. low level active enzyme (12% normal) generated from leakage normally mRNA sustained life. 61 refs., 9 figs., 3 tabs.