Moreover, since telomere dysfunctions trigger a profound inhibition of mitochondrial biogenesis through p53-mediated suppression of both PGC-1α and PGC-1β [124], loss of function of this tumor suppressor adds a layer of complexity to the amount of stress that a cancer cell can adapt to before triggering mitochondria-mediated apoptosis. The gene discussed is PPARGC1B; the disease is cancer.