Genetics of intervertebral disc disease: A review.

Intervertebral disc disease (IVDD) is a common musculoskeletal disease affecting about 5% of all individuals. It is characterized by lumbar disc herniation, which causes nerve root irritation, either mechanically or via inflammatory mediators, and results in radiating pain, known as sciatica. Numerous studies have been conducted to identify the causes and risk factors for IVDD. Lifting heavy loads, torsional stress, and motor vehicle driving are among the best-identified environmental risk factors. However, it has become evident recently from family and twin studies that genetic factors may also be important in IVDD. This hypothesis was strengthened by the identification of two collagen IX alleles associated with sciatica and lumbar disc herniation. In addition, disc degeneration has been shown to be related to an aggrecan gene polymorphism, a Vitamin D receptor and matrix metalloproteinase-3 gene alleles. This review highlights the genetic role and occupational aspects of IVDD.