These included genes linked to Fraser syndromes (Fras1, Frem2, Grip1), osteogenesis imperfecta and related bone fragility (Bmp1a, Col1a1, Col1a2, Col2a1), skeletal dysplasia (Fgfr3, Flnb, Nek1, Ebp), limb and heart malformations (Tbx5a), and cutaneous or connective tissue disorders (St14, Lmna, Pex1, Aspa). This evidence concerns the gene COL2A1 and connective tissue disorder.