Finally, we extended our screening to include exon 50 of COL2A1 since a recurrent mutation (p.Gly1170Ser) in this exon has been shown to cause Legg-Calve-Perthes (LCP) disease in four families [Miyamoto et al., 2007; Su et al., 2008], and there is clear clinical overlap between LCP and MED [Herring and Hotchkiss, 1987; Ikegawa et al., 1991]. The gene discussed is COL2A1; the disease is Legg-Calve-Perthes disease.