Mitochondrial neurogastrointestinal encephalopathy (MNGIE) is a rare, complex mitochondrial disorder with variable phenotypes caused by a defect in the TYMP gene that codes for the thymidine phosphorylase enzyme.
She developed gastrointestinal symptoms, dysarthria, dysphagia and weakness, and MNGIE was considered due to its low TP levels and improvement after platelet transfusions.
Deficiency of the cytosolic enzyme thymidine phosphorylase (TP) causes a multisystem disorder called mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) syndrome.
We found pathogenic mutations on TP gene only in the MNGIE syndrome group: all the MNGIE patients were compound heterozygous or homozygous for mutations in the TP gene.
We have identified homozygous or compound-heterozygous thymidine phosphorylase gene mutations in 35 MNGIE patients (21 families) from diverse ethnic groups, including: Ashkenazi Jewish, Western European, Jamaican, Hispanic, and Japanese.