and aging. With degeneration, the disc components - the nucleus pulposus and annulus fibrosus - become exposed to altered loads. Specifically, the nucleus becomes fibrous and stiff and less able to bear load. Excess load is transferred to the annulus, which may then develop fissures as a result. If the fissures reach the periphery of the annulus, the nuclear material can pass through as a disc herniation.

Mutations in several genes have been implicated in intervertebral disc degeneration. Probable candidate genes include type I collagen