Further analyses certainly are necessary to evaluate the importance of the upregulation of TRAIL expression in distinct IVD regions within the apoptotic process, where the TRAIL/DR4/DR5 axis and the downstream activation of both initiator and activator caspases in IVD cells of dogs suffering from DDD are investigated in depth.75 This evidence concerns the gene TNFRSF10A and Dowling-Degos disease 1.