Genetic testing and genetic findings in Korean children with cerebral palsy

AIM: To determine the testing rate and pathogenic or probably pathogenic positivity rate of genetic testing in children with cerebral palsy (CP) in Korea using data from a nationwide multicentre registry, and to identify clinical features associated with positive genetic findings. METHOD: Baseline data from 539 children enrolled in the Korean Cerebral Palsy Registry were analysed. Genetic testing modalities included chromosomal microarray, whole-exome sequencing, whole-genome sequencing, clinical exome sequencing, and karyotyping. Pathogenic and probably pathogenic variants were categorized into primary genetic contributors to CP, genetic motor disorders outside the CP construct, diagnostic interface cases between CP and other genetic motor disorders, and co-occurring genetic conditions. RESULTS: Among 539 children (304 males), 92 (17.1%) underwent genetic testing, yielding a pathogenic or probably pathogenic positivity rate of 37.0%. Primary genetic contributors to CP accounted for 35.3% of positive results and genetic motor disorders outside the CP construct for 8.8%. Positive findings were more frequent in children born at 32 or more weeks without perinatal risk factors, or presenting dyskinetic features or atypical magnetic resonance imaging patterns. Clinicians most frequently requested testing because of absent perinatal risk factors or atypical magnetic resonance imaging findings. INTERPRETATION: Genetically relevant variants were identified in over one-third of tested children, especially those with atypical phenotypes or absent perinatal risk factors. These findings support incorporating genomic testing into routine CP evaluation, particularly for cryptogenic or atypical presentations.