TYRA-300 was studied in a Tg-CMVCre/+/Fgfr3Y367C/+ mouse model, which, while corresponding to the human FGFR3 Y373C mutant responsible for thanatophoric dysplasia, type I, displays a phenotype similar to that of human ACH and has been previously used to test the preclinical efficacy of other therapies in this context (21, 28, 29, 34–36). The gene discussed is FGFR3; the disease is achondroplasia.