WIF1 and Hip dysplasia: Several genes, including WNT inhibitory factor 1 (WIF1, OMIM * 605186), Collagen type XI alpha 2 chain (COL11A2, OMIM * 120290), and Pregnancy-associated plasma protein A2 (PAPPA2, OMIM * 176385), were shown to increase susceptibility to DDH through candidate association studies in one population [7–10].