Missense mutations in BMP antagonist Noggin cause tyrosine kinase-like orphan receptor 2 (ROR2)-negative brachydactyly type B (BDB2; OMIM611377), which is characterized by hypoplasia/aplasia of distal phalanges in combination with distal symphalangism and fusion of carpal/tarsal bones242. Here, ROR2 is linked to brachydactyly type B.