ABSTRACT
@#Abstract： Objective To investigate the clinical characteristics and pathogenic genetic mutation of a case with encephalopathy due to defective mitochondrial and peroxisomal fission-1 (EMPF1). Methods The clinical data and genetic test results of a patient with EMPF1 admitted to the Department of Pediatrics, the Affiliated Hospital of Xiangya Medical College of Central South University in August 2020 were retrospectively analyzed. Results An 8-year-old girl, her main clinical features were developmental regression, microcephaly, hypotonia, refractory epilepsy, cranial MRI suggesting brain atrophy and abnormal signals in the right temporal-occipital-parietal cortex, aEEG showing slow wave discharge in the right hemisphere; Whole-exome sequencing of families suggested that the child had a heterozygous missense variant at the c.1040C>G site in the DNM1L gene and the verification results by Sanger sequencing showed that her parents had no variant in this site, which was a novel mutation in accordance with autosomal dominant inheritance; bioinformatics analysis predicted that the mutation was pathogenic. After 2 years of outpatient follow-up, the patient's condition was stable after mitochondrial cocktail therapy and antiepileptic drugs, no epileptic seizure occurred in the past year, mental state and swallowing function improved, and she could be fed orally with occasional nausea and vomiting. Conclusions The main clinical manifestations of EMPF1 are psychomotor developmental delay or regression, dystonia, limb paralysis, epilepsy and so on. According to the clinical phenotype and genetic test results, the rare disease can be diagnosed early.
ABSTRACT
Objective:To summarize the clinical features of developmental epileptic encephalopathy children with DNM1 gene variants. Methods:The genotypes and clinical features of 15 children with DNM1 variants related epilepsy in the Department of Pediatrics, Peking University First Hospital from June 2017 to October 2021 were retrospectively analyzed. Results:A total of 8 male and 7 female epilepsy patients with DNM1 gene variants with the age of seizure onset ranging from 15 days to 22 months were recruited, median age was 8 months.All cases belonged to de novo heterozygous variants of the DNM1 gene, including 13 cases of missense variants, 1 case of frame shift variant and 1 case of nonsense variant, 8 cases of ectopic sites have not been reported.Multiple seizure types were observed, including epileptic spasms in 15 patients, focal seizure in 9 patients, atypical absence seizure in 2 patients and tonic seizure in 2 patients.There were various types of seizures in 7 children.Nine cases occurred as infantile spasm for the first time.All 15 patients showed varied degrees of development delay, among them, 11 cases had developmental retardation before epilepsy.Three patients had slow rhythm of electroencephalogram background activity, the electroencephalography showed hypsarrhythmia in 13 patients; clinical seizures were detected in 8 cases, among them, epileptic spasms were captured in 7 patients, tonic seizure was captured in 1 patient.Widened frontotemporal subarachnoid space, cerebral atrophy, and corpus callosum dysplasia were examined in 6, 2 and 3 patients by cranial magnetic resonance imaging, respectively.All 15 cases were diagnosed as developmental epileptic encephalopathy, of which 13 cases were consistent with infantile spasms.The age of the last follow-up ranged from 1 year old to 7 years old.After multi-antiepileptic drug treatment, 2 patients were remission, 1 patient(small size of identical twins) died of severe pneumonia at the age of 2 years, and 12 patients still had intermittent seizures, of which 1 patient was transformed from infantile spasms to Lennox-Gastaut syndrome. Conclusions:The onset age of developmental epileptic encephalopathy caused by the DNM1 gene variant usually begins in the infantile period, the peak onset age was 8 months.The main types of seizures include epileptic spasms and focal seizures, developmental retardation can occur before seizures.The clinical manifestations are mostly infantile spasms syndrome, and some children can be transformed into Lennox-Gastaut syndrome.
ABSTRACT
O colapso induzido pelo exercício (EIC) é considerado uma síndrome autossômica recessiva que afeta principalmente cães da raça Labrador Retriever. A doença é caracterizada por fraqueza muscular e colapso após exercício intenso. Usualmente, ocorre recuperação clínica após o episódio, mas alguns animais podem vir a óbito. Os sinais clínicos são decorrentes do polimorfismo de base única (SNP) c.767G>T no gene Dynamin 1 (DNM1). O objetivo deste trabalho foi determinar a ocorrência deste SNP em 321 cães da raça Labrador Retriever do Estado de São Paulo. Primers específicos para a amplificação de todo o exon 6 do gene DNM1 foram usados nas PCRs utilizando DNA a partir de amostras de sangue ou swab bucal, a avaliação final foi realizada com sequenciamento direto dos produtos da PCR. Dentre os 321 animais estudados, 3,4 % (11/321) eram homozigotos para o SNP c.767G>T no gene DNM1 e 24,6% (79/321) eram heterozigotos. Somente um dos 11 animais homozigotos apresentavam sinais clínicos compatíveis com a EIC. Este é o primeiro estudo sobre a ocorrência deste SNP no Brasil e considerando que quase 25% dos animais estudados eram heterozigotos, a genotipagem dos animais para este SNP pode ser importante antes dos acasalamentos para cães desta raça. A EIC deve ser considerada nos diagnósticos diferenciais de enfermidades neuromusculares em cães da raça Labrador Retriever.
The exercise-induced collapse (EIC) is considered an autosomal recessive syndrome that mainly affects Labrador Retriever dogs. The disease is characterized by muscle weakness and collapse after intense exercise. Recovery usually occurs after exercise but some animals may die. The clinical signs occurs due to the single-nucleotide polymorphism (SNP) c.767G>T in Dynamin 1 (DNM1) gene. The aim of this study was to evaluate the occurrence of this SNP in 321 Labrador Retriever dogs from São Paulo state. Specific primers for amplification of the entire exon 6 of the DNM1 gene were used in a PCR performed with DNA from blood or buccal swab samples, direct sequencing was performed for the final evaluation. Among 321 animals studied, 3.4% (11/321) of animals were homozygous for the DNM1 SNP (c.767G>T) and 24.6% (79/321) were heterozygous. Only one of the 11 homozygous animals in this study had previous clinical signs compatible with this disease. This is the first study that evaluated the occurrence of DNM1 SNP (c.767G>T) gene in Brazil and considering that almost 25% of the studied animals were heterozygous, the routinely evaluation of this SNP may be important before this breed mating The EIC should be include in the differential diagnosis of neuromuscular diseases in Labrador Retriever dogs.