RUNX2 and achondroplasia: For instance, Cissé et al (2024) reported that a specific mutation (c.925C>T; p.Gln309X) on the RUNX2 (Runt-related transcription factor 2) gene, which is responsible for regulating the differentiation of mesenchymal stem cells into bone-forming cells, resulted in severe parietal bone dysplasia in a 20-month-old girl.[5] Nagata et al (2020) identified a novel mutation (c.1133G>A; p.S378N) in the fibroblast growth factor receptor 3 gene of a 3-year-old girl using whole genome sequencing.[6] The novel mutation has been identified as the cause of achondroplasia in this proband.