Phenotypic and Genetic Complexity in Pediatric Movement Disorders

Area of Science:

• Genetics
• Neurology
• Pediatrics

Background:

• Diagnosing pediatric movement disorders is challenging due to complex and evolving clinical phenotypes.
• Traditional phenotype-driven diagnostic strategies have limitations in identifying underlying genetic causes.

Purpose of the Study:

• To evaluate the clinical and genetic features of pediatric patients with movement disorders using whole-exome sequencing (WES).
• To demonstrate the diagnostic utility and clinical benefit of WES in this patient cohort.

Main Methods:

• Whole-exome sequencing (WES) was performed on 75 pediatric patients presenting with diverse movement disorders.
• Clinical and genetic data were analyzed to identify causative variants and assess diagnostic yield.

Main Results:

• WES identified 42 variants in 37 genes in 56.0% of patients.
• Diagnostic yield varied by phenotype, with dystonia (84.6%) and tremor (100%) showing higher rates.
• Congenital hypotonia and epilepsy were common co-occurring phenotypes in genetically diagnosed patients.

Conclusions:

• Early application of WES provides a high diagnostic rate for pediatric movement disorders, overcoming limitations of traditional methods.
• Genetic diagnoses facilitated changes in clinical management for 6.7% of patients, including targeted treatments and systemic surveillance.
• WES expands the understanding of clinical spectra and enables personalized treatment strategies.