Mutations in the LDLa, EGF-like domain or in the first and second β-propeller domains cause Cenani–Lenz Syndrome (CLS) [67]; mutations in the central cavity of the third β-propeller domain cause sclerosteosis-2 [47,48]; and those in the fourth β-propeller domain or in the EGF-like domain cause isolated bilateral syndactyly [68,69]. This evidence concerns the gene EGF and sclerosteosis.