In this study, we describe a severely emaciated male proband with MNGIE carrying compound heterozygous TYMP variants: a novel variant (c.1268T > G, p.Leu423Arg) from his asymptomatic mother and a previously reported variant (c.131G > C, p.Arg44Pro) from his asymptomatic father, consistent with autosomal recessive inheritance. This evidence concerns the gene TYMP and mitochondrial neurogastrointestinal encephalomyopathy.