RESUMEN
Objective:To summarize the clinical phenotype and genetic characteristics of children with neurodegeneration caused by UBTF gene mutations in childhood. Methods:The clinical and genetic data of 3 children with neurodegeneration in childhood diagnosed in the Department of Neurology, Children′s Hospital Affiliated to Zhengzhou University from February 2020 to January 2023 were retrospectively analyzed. All the 3 probands were found having UBTF gene mutations through the whole exome gene sequencing, and the first generation Sanger sequencing method was used to verify the UBTF gene in their family members. The variation characteristics of the UBTF gene were analyzed, and the treatment and follow-up results of the 3 children were summarized. Results:Among the 3 children with childhood onset neurodegeneration, 2 were male and 1 female, aged 9 months, 4 years and 6 months after birth, respectively. The clinical phenotypes mainly included motor retardation, speech and mental retardation, and dystonia. Among them, case 1 and case 2 had seizures, case 1 had dysphagia, feeding problems, no weight gain and ataxia. Brain MRI plain scan showed that case 1 and case 2 had different degrees of cerebral atrophy, case 1 had hypoplasia of corpus callosum, ventricle expansion and softening focus, and case 3 showed non-specific widening of the subarachnoid space. There were no abnormalities in the chromosome copy number variation and mitochondrial ring gene testing in the 3 children; the whole exon gene testing suggested the de novo missense variant in the UBTF gene [NM_014233.4: c.1414(exon14) G>A (p.Gly472Ser), c.1392(exon14)G>T(p.Lys464Asn)] and the maternal nonsense variant [NM_014233.4:c.520C>T(p.Arg174 *)], which were unreported site variants. In terms of treatment, the 3 children received comprehensive rehabilitation function training, and achieved a certain degree of language and intelligence improvement. Seizure control was effectively managed in case 1 with a single antiepileptic drug. Epileptic seizures were effectively treated and controlled in case 2 using more than 4 types of antiepileptic drugs. Conclusions:Neurodegenerative changes caused by UBTF gene mutations in childhood are relatively rare, and some cases may be accompanied with brain atrophy. De novo missense variation and maternal nonsense variation of the UBTF gene are the genetic etiology of the 3 probands.