Except for surgery treatment and population incidence, more studies focused on the genetic level of OPLL and documented many genes or gene loci of interest involved in mediating the molecular and genetic pathobiology of OPLL, including COL6A1, COL11A2, TGFβ-1, and IL17RC (31, 32). This evidence concerns the gene COL6A1 and ossification of the posterior longitudinal ligament of the spine.