COL1A2 and connective tissue disorder: For instance, mutations in COL1A2, COL3A1, and COL5A2 human genes (identified as hub genes in the present research) are at least in part the genetic basis of the Ehlers-Danlos syndrome: a systemic connective tissue disorder caused by defects in fibrillar collagen deposition (Nuytinck et al., 2000; Mao & Bristow, 2001; Malfait et al., 2005).