Richardson et al. [17] showed that HIF-1α, GLUT-1, GLUT-3, and GLUT-9 were co-expressed in normal human IVDs, and an increase in HIF-1α expression was associated with an increase in the expression of GLUT-1, GLUT-3, and GLUT-9 in NP cells; however, this association has not been observed in AF cells. The gene discussed is HIF1A; the disease is atrial fibrillation.