Biallelic TYMP variants result in the mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), a juvenile-onset disorder with progressive course and fatal outcome. Milder late-onset (>40 years) form has been rarely described. Gene panel sequencing in a cohort of 60 patients featuring muscle accumulation of mitochondrial DNA (mtDNA) deletions detected TYMP defects in three subjects (5%), two of them with symptom onset in the fifth decade. One of the patients only displayed ptosis and ophthalmoparesis. Biochemical and molecular studies supported the diagnosis. Screening of TYMP is recommended in adult patients with muscle mtDNA instability, even in the absence of cardinal MNGIE features.

双等位基因 TYMP变异会导致线粒体神经胃肠道脑病（MNGIE），这是一种少年发作性疾病，具有进行性病程和致命的后果。较轻的迟发性（> 40岁）形式很少被描述。60名患者的基因组测序发现了线粒体DNA（mtDNA）缺失的肌肉积累TYMP三名受试者（5％）有缺陷，其中两个在第五个十年出现症状。其中一名患者仅出现下垂和眼睑轻瘫。生化和分子研究支持了该诊断。筛选TYMP 建议在肌肉mtDNA不稳定的成年患者中使用，即使在没有主要MNGIE功能的情况下也是如此。