Clinical phenotypes study of autosomal recessive cerebellar ataxia type 1 caused by SYNE 1 gene mutations / 中华神经科杂志

Objective To investigate the clinical features of autosomal recessive cerebellar ataxia type 1 (ARCA1) and analyze the pathogenic variants in SYNE 1 gene. Methods A cohort of 80 probands of autosomal recessive cerebellar ataxia pedigrees excluding Friedreich ataxia were detected by whole?exome sequencing technology. Potential pathogenic variants were confirmed by Sanger sequencing. Clinical phenotypes of positive patients were analyzed in detail. Results Three pedigrees of ARCA1 caused by SYNE 1 gene variants were found. The proband of pedigree 1 carried homozygous frameshift mutation c.12670dupC(p.L4224fs), presented as pure cerebellar ataxia. The proband of pedigree 2 carried compound heterozygous mutations c. 20826+1G>T and c. 25954C>T(p. R8652X), presented as cerebellar ataxia plus upper motor neuron dysfunction. The proband of pedigree 3 carried compound heterozygous mutations c.21955C>T(p.Q7319X) and c.23777C>A(p.T7926K), presented as mental behavior and cognitive impairment, cerebellar ataxia and upper motor neuron dysfunction. Brain MRI showed obvious cerebellar atrophy in all patients, and the fronto?temporal lobes were also found slight atrophy in proband of pedigree 3. Conclusions The phenotype of ARCA1 caused by SYNE 1 gene mutations is characterized by cerebellar ataxia, maybe accompanied with motor neuron damage and cognitive dysfunction. ARCA1 is a rare form of autosomal recessive cerebellar ataxia in Chinese population, with a complex phenotype. The use of next generation sequencing allows the rapid analysis of ARCA1, and will likely further expand genotype?phenotype correlations.

Analysis of SYNE1 gene variant in an infant featuring epilepsy and developmental disorders / 中华医学遗传学杂志

Objective@#To explore the clinical features and molecular basis for a child featuring infantile epilepsy and developmental disorders.@*Methods@#Clinical data and peripheral blood samples of the child and his parents were collected. The coding regions of genes associated with nervous system development were subjected to target region capture sequencing.@*Results@#The child developed generalized spasm at 3 months and was diagnosed with epilepsy at 6 months of age. He was treated with Depakin but was diagnosed with mental retardation and developmental retardation at 3 years of age. A novel heterozygous c. 3842T>G variant of the SYNE1 gene was detected. His father was found to carry the same variant and had a history of convulsions in infancy but with no mental or developmental anomalies.@*Conclusion@#A novel variant of SYNE1 gene was identified in this child, and the prognosis may be poor.

Clinical phenotypes study of autosomal recessive cerebellar ataxia type 1 caused by SYNE 1 gene mutations / 中华神经科杂志

Objective@#To investigate the clinical features of autosomal recessive cerebellar ataxia type 1 (ARCA1) and analyze the pathogenic variants in SYNE 1 gene.@*Methods@#A cohort of 80 probands of autosomal recessive cerebellar ataxia pedigrees excluding Friedreich ataxia were detected by whole-exome sequencing technology. Potential pathogenic variants were confirmed by Sanger sequencing. Clinical phenotypes of positive patients were analyzed in detail.@*Results@#Three pedigrees of ARCA1 caused by SYNE 1 gene variants were found. The proband of pedigree 1 carried homozygous frameshift mutation c.12670dupC(p.L4224fs), presented as pure cerebellar ataxia. The proband of pedigree 2 carried compound heterozygous mutations c.20826+1G>T and c.25954C>T(p.R8652X), presented as cerebellar ataxia plus upper motor neuron dysfunction. The proband of pedigree 3 carried compound heterozygous mutations c.21955C>T(p.Q7319X) and c.23777C>A(p.T7926K), presented as mental behavior and cognitive impairment, cerebellar ataxia and upper motor neuron dysfunction. Brain MRI showed obvious cerebellar atrophy in all patients, and the fronto-temporal lobes were also found slight atrophy in proband of pedigree 3.@*Conclusions@#The phenotype of ARCA1 caused by SYNE 1 gene mutations is characterized by cerebellar ataxia, maybe accompanied with motor neuron damage and cognitive dysfunction. ARCA1 is a rare form of autosomal recessive cerebellar ataxia in Chinese population, with a complex phenotype. The use of next generation sequencing allows the rapid analysis of ARCA1, and will likely further expand genotype-phenotype correlations.