FGF18 and cleft palate: Studies have identified regulatory roles between FGF18 and fox family members such as FOXF2 in cleft palate development (Xu et al., 2016), however, there is little to no research that has gone into establishing FOXN2 in the development of PTOA or its regulation by FGF18 in PTOA, and how their interaction may lead to or prevent the onset of osteoarthritis.