Abstract:

Genetic factors are common causes of early infantile-onset epileptic encephalopathy. The pathogenicity variation of a child with early infantile-onset epileptic encephalopathy was reported in this paper. The boy was 4 months and 27 days old. He had recurrent convulsions for more than 20 days, characterized by convulsive seizures and developmental retardation. The proband's parents had no abnormal phenotype. The proband had compound heterozygous variation of c.287G>A (p.Arg96His) and c.283G>A (p.Val95Ile) in PARS2 gene. The former was derived from the mother, and the latter from the father. Among them, the former phenotype has not been reported, while the latter variant of C. 283G>A has been reported in the past. According to the guidelines of the American College of Medical Genetics and Genomics, both of them are considered to be of "unknown significance". After 6 weeks of oral treatment with topiramate and nitrazepam, seizure was controlled, but the child still had significant psychomotor developmental retardation and hypotonia. The results suggested that a novel compound heterozygous variation of PARS2 gene is the pathogenic variation of the child with early infantile-onset epileptic encephalopathy in this family, which provides a basis for genetic counseling in this family. Epileptic encephalopathy caused by PARS2 gene variation still has severe developmental retardation even when seizure is controlled.

Key words: PARS2 gene, epilepsy, encephalopathy, infant