ODC1 and Global developmental delay: This one variant had the highest potential rare disease phenotypic risk (based on Geno2MP and CADD) within a 1.4 million base pair region around ODC1. Based on Bupp et al. and Rodan et al. [31,32], there is already a clear establishment of gain-of-function variants within ODC1 to developmental delay, while inhibition of ODC with DFMO in early development impacts many biological pathways, suggesting a tight control of ODC1 in development.