B4GALT7 and Larsen syndrome: Mutations in B4GALT7 cause skeletal dysplasia, Ehlers-Danlos syndrome and Larson of Reunion Island syndrome (LRS), since B4GALT7 is correlated with the initiation of glycosaminoglycan side chain synthesis of PGs (Mihalic Mosher et al., 2019; Arunrut et al., 2016; Sandler-Wilson et al., 2019; Delbaere et al., 2020; Caraffi et al., 2019).