Age dependant reduction in PGs, IVD hydration, ECM biomechanical competence. Early IVDD in ChD canine compared to non‐ChD due to relative decline in notochordal cell numbers. SM/J mouse early onset spontaneous IVDD. NP cell death, degeneration of NP, AF, CEP. Elevated expression of Col10a1, Ctgf, Runx2 and chondrocyte hypertrophy. The gene discussed is RUNX2; the disease is coronary artery disorder.