PAPPA2 and Hip dysplasia: Christians and colleagues [68,77] also reported non-size dependent differences in the shape of the pelvic girdle (ischium shape, pubis length and ilium width) and mandible (smaller distance between the tips of the angular and coronoid processes) of whole Pappa2 KO mice, suggesting that PAPP-A2 deficiency-related disproportionality of pelvic gridle shape may contribute to hip dysplasia in humans and result in difficulties in giving birth [82,83].