PDGFRA and fibrodysplasia ossificans progressiva: In addition to defining the time course of HO progression through 6-weeks-of-age and the effects of progressive HO on survival and morbidity, the analysis revealed the formation of osteochondromas in Pdgfrα-R206H mice, a phenotype present in FOP patients but not previously described in other FOP mouse models (Chakkalakal et al., 2016; Dey et al., 2016; Hatsell et al., 2015; Lees-Shepard et al., 2018).