In this respect, transcriptome analysis also aimed to identify differentially expressed genes and dysregulated biological pathways that may contribute to the pathogenesis observed in patients carrying loss-of-function variants in KMT5B. While peripheral blood RNA-sequencing provides a minimally invasive approach to explore gene expression alterations, it is important to acknowledge its limitations in the context of neurodevelopmental disorders. The gene discussed is KMT5B; the disease is neurodevelopmental disorder.