Fibroblasts from OPLL patient ligaments were transfected with SOX8 knockdown (sh‐SOX8), SOX8 overexpression (OE‐SOX8), or control vectors (Blank, sh‐NC, and VEC) and underwent a week‐long osteogenic induction in vitro. The gene discussed is SOX8; the disease is ossification of the posterior longitudinal ligament of the spine.