Clinical Utility of Multitissue Genomic Arrays in Diagnosing Pigmentary Mosaicism Associated with Neurodevelopmental Delay

Genomic mosaicism is underdiagnosed owing to its variable tissue distribution and the limitations of single-tissue testing. Cytogenomic techniques applied across multiple tissues can uncover clinically actionable variants and clarify genotype-phenotype relationships. DNA from 21 patients (14 females and 7 males) with pigmentary mosaicism and global developmental delay was analyzed. Each patient underwent G-band karyotyping and array (Infinium CytoSNP-850K) on peripheral blood, skin fibroblasts, and buccal mucosa samples.