[Analysis of PDHA1 gene variant in a patient with pyruvate dehydrogenase E1alpha deficiency and pyramidal tract involvement].

To explore the genetic basis for a patient with episodic ataxia and pyramidal tract signs.The patient was subjected to high-throughput sequencing, Sanger sequencing and analysis of dynamic variant site associated with spinocerebellar ataxias (SCA).The patient was an adolescent male presenting with episodic ataxia, bilateral knee hyper-reflexia and ankle clonus. By genetic testing, he was found to harbor a c.1159-1162dupAAGT variant of PDHA1 gene. The same variant was not found in his parents and elder sister. No abnormalities were found by SCA dynamic variant screening. The patient was diagnosed as pyruvate dehydrogenase E1alpha deficiency due to variant of the PDHA1 gene.The de novo c.1159-1162dupAAGT variant of the PDHA1 gene probably underlies the disease in the proband. Patients with pyruvate dehydrogenase E1alpha deficiency have complex phenotypes and very few have pyramidal tract involvement, which may be attributed to abnormal early neuronal development.