Abstract
Molecular diagnosis of N-acetylglutamate synthase deficiency (NAGSD) has become possible now that the corresponding gene has been identified. We describe the genetic analysis of a patient with NAGSD using low-level transcripts derived from cultured fibroblasts. One defective allele (c.1306–1307insT) was detected by PCR amplification. However, the transcript from a second mutation (IVS3-2A>T), causing aberrant splicing with the generation of a premature termination codon, was not detected until interference of nonsense-mediated mRNA decay was abrogated by the translation inhibitor cycloheximide. We demonstrate that low-level transcripts in cells that do not express significant enzyme activity are a valuable tool for molecular studies of genetic alterations, and suggest routine abrogation of nonsense-mediated mRNA decay using cycloheximide when transcript analysis is performed.
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Häberle, J., Denecke, J., Schmidt, E. et al. Diagnosis of N-acetylglutamate synthase deficiency by use of cultured fibroblasts and avoidance of nonsense-mediated mRNA decay. J Inherit Metab Dis 26, 601–605 (2003). https://doi.org/10.1023/A:1025912417548
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DOI: https://doi.org/10.1023/A:1025912417548