[Clinical and genetic characteristics ofgene related developmental delay].

Researchers studied 10 children with genetic changes that cause developmental delays. Most children had moderate to severe delays in learning and development. Some also had autism or seizures. Brain scans showed problems in 4 out of 6 children tested. The genetic changes were mostly new (not inherited from parents). Children with certain types of genetic changes had more severe delays, suggesting the location of the genetic change affects how serious the symptoms are.

This case series examined 10 children (7 males, 3 females, aged 27 days to 5 years 9 months) with gene variants causing developmental delay. Nine patients showed global developmental delay (2 mild, 4 moderate, 3 severe cases), with 3 having autism spectrum disorder and 2 having epilepsy. Brain MRI abnormalities were found in 4 of 6 patients tested, including delayed myelination and frontal lobe changes. All cases had point variants, with 9 being de novo and 1 maternally inherited.

Four patients had variants in the S4 segment of a specific protein domain, which correlated with more severe developmental delays. The study suggests voltage-sensing domain dysfunction in sodium channels may be a key mechanism underlying neurodevelopmental impairments.

Early developmental assessment is crucial for children with these gene variants. Most will require moderate to intensive interventions. Autism screening should be standard practice. Brain imaging may help identify structural abnormalities. Genetic variant location may help predict severity and guide intervention planning.

Very small sample size (n=10) limits generalizability. Case series design provides limited evidence compared to controlled studies. Incomplete data collection (only 6 patients had MRI, 9 had developmental assessments). Short observation period may miss long-term outcomes.

To explore the genotype and the clinical phenotype of-related developmental delay in children.A case series study was adopted. Collect clinical data from 10 cases of children withgene variants diagnosed with global developmental delay/intellectual disability who were admitted to the Children's Hospital between July 2019 and March 2023. Summarize the clinical phenotype and genotype based on clinical data such as general information, clinical manifestations, imaging examinations, laboratory tests, genetic testing results, and comprehensive pediatric neuropsychological development assessment.A total of 10 patients were recruited, including 7 males and 3 females, with an age range of 27 days to 5 years and 9 months. 9 patients underwent children's neuropsychological and behavioral assessments, and the results were consistent with global developmental delay, including 2 mild cases, 4 moderate cases, and 3 severe cases. 3 cases had autism spectrum disorder, and 2 cases had epilepsy. 6 patients underwent complete head MRI examination, and 4 of them showed abnormalities, including delayed myelination, widening of the local extra brain space in the frontal lobe, and abnormal frontal lobe morphology. All 10 cases had point variants.

Among them, 9 cases areand 1 case is maternal inheritance. Out of 10 cases, there were 5 cases with copy number variations, but all of them were of unknown significance. Among the 10 variants, 8 have been reported and 2 have not been reported, namely c.4145A>T(p.N1382I) and c.4937T>A(p.I1646N). In this study, 4 out of 10 patients withvariants had variation sites located in the S4 segment of domain which constitute Nav1.2, the sodium ion channel encoded by.

The developmental quotient level was lower when the variation sites were located in the S4 segment of domain, and the difference was statistically significant (=-3.101,=0.017), indicating that the severity of developmental delay may be related to the localization of amino acids corresponding to variant sites within the protein domain.mutations are strongly associated with diverse neurodevelopmental disorders. In this study, the phenotypic spectrum ofvariants encompassed epilepsy, global developmental delay, and autism spectrum disorder. Affected individuals exhibited early-onset developmental delays, predominantly moderate to severe in severity. Voltage-sensing domain dysfunction in sodium channels may constitute a critical pathomechanism underlying neurodevelopmental impairments.

Further electrophysiological characterization and molecular mechanistic studies are warranted todelineate the genotype-phenotype correlations between specific variant loci and clinical severity.