FLNA genomic rearrangements in a 391 French bilateral periventricular nodular heterotopia cohort: prevalence and phenotypic correlations

BACKGROUND: gene dosage anomalies and investigates genotype-phenotype correlations in a large cohort of French patients with BPNH. METHODS: A retrospective observational study was conducted on 391 individuals diagnosed with BPNH confirmed by brain MRI. Sequencing analysis using Sanger or next-generation sequencing was complemented by targeted array-comparative genomic hybridisation to identify copy number variants (CNVs). RESULTS: gene. This del-dup was associated with a milder phenotype, whereas smaller de novo deletions correlated with severe outcomes. Mosaicism was also detected in three cases. CONCLUSION: CNV analysis, particularly for recurrent deletions and mosaicism, is essential in the genetic evaluation of BPNH. Integrating CNV detection with SNV analysis improves diagnostic accuracy and enhances understanding of genotype-phenotype correlations.