Late-onset MNGIE without peripheral neuropathy due to incomplete loss of thymidine phosphorylase activity

Roberto Massa, Alessandra Tessa, Maria Margollicci, Vanna Micheli, Andrea Romigi, Giulia Tozzi, Chiara Terracciano, Fiorella Piemonte, Giorgio Bernardi, Filippo M. Santorelli

Research output: Contribution to journalArticlepeer-review


Mitochondrial NeuroGastroIntestinal Encephalomyopathy (MNGIE) is an autosomal recessive disorder characterized by severe gastrointestinal dysmotility, cachexia, peripheral neuropathy, ptosis, ophthalmoplegia, and leukoencephalopathy with early onset and severe prognosis. Mutations in the TYMP/ECGF1 gene cause a loss of thymidine phosphorylase catalytic activity, disrupting the homeostasis of intramitochondrial nucleotide pool. We report a woman with a very late onset of MNGIE, lacking peripheral neuropathy. Thymidine phosphorylase activity was markedly reduced in cultured fibroblasts, but only mildly reduced in buffy coat, where the defect is usually detected, and plasma thymidine was mildly increased compared to typical MNGIE patients. TYMP/ECGF1 analysis detected two heterozygous mutations, including a novel missense mutation. These findings indicate that a partial loss of thymidine phosphorylase activity may induce a late-onset and incomplete MNGIE phenotype.

Original languageEnglish
Pages (from-to)837-840
Number of pages4
JournalNeuromuscular Disorders
Issue number12
Publication statusPublished - Dec 2009


  • Late-onset
  • Mitochondrial disease
  • Peripheral neuropathy
  • Thymidine phosphorylase
  • TYMP/ECGF1 mutations

ASJC Scopus subject areas

  • Genetics(clinical)
  • Clinical Neurology
  • Pediatrics, Perinatology, and Child Health
  • Neurology


Dive into the research topics of 'Late-onset MNGIE without peripheral neuropathy due to incomplete loss of thymidine phosphorylase activity'. Together they form a unique fingerprint.

Cite this