Previous study have shown that DLX3 acted as a molecular switch that regulated RUNX2 expression throughout bone formation, we here tested the ability of mutant DLX3 to bind RUNX2 promoter to determine whether deceased osteogenic potential associated with TDO-BMSCs were directly due to DLX3 mutation. The gene discussed is RUNX2; the disease is tricho-dento-osseous syndrome.