A functional SNP in CILP, encoding cartilage intermediate layer protein, is associated with susceptibility to lumbar disc disease

Nat Genet. 2005 Jun;37(6):607-12. doi: 10.1038/ng1557. Epub 2005 May 1.


Lumbar disc disease (LDD) is caused by degeneration of intervertebral discs of the lumbar spine. One of the most common musculoskeletal disorders, LDD has strong genetic determinants. Using a case-control association study, we identified a functional SNP (1184T --> C, resulting in the amino acid substitution I395T) in CILP, which encodes the cartilage intermediate layer protein, that acts as a modulator of LDD susceptibility. CILP was expressed abundantly in intervertebral discs, and its expression increased as disc degeneration progressed. CILP colocalized with TGF-beta1 in clustering chondrocytes and their territorial matrices in intervertebral discs. CILP inhibited TGF-beta1-mediated induction of cartilage matrix genes through direct interaction with TGF-beta1 and inhibition of TGF-beta1 signaling. The susceptibility-associated 1184C allele showed increased binding and inhibition of TGF-beta1. Therefore, we conclude that the extracellular matrix protein CILP regulates TGF-beta signaling and that this regulation has a crucial role in the etiology and pathogenesis of LDD. Our study also adds to the list of connective tissue diseases that are associated with TGF-beta.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Case-Control Studies
  • Chromosomes, Human, Pair 15
  • Disease Susceptibility
  • Extracellular Matrix Proteins / genetics*
  • Female
  • Humans
  • Intervertebral Disc Displacement / genetics*
  • Lumbar Vertebrae*
  • Male
  • Middle Aged
  • Polymorphism, Single Nucleotide
  • Pyrophosphatases / genetics*
  • Signal Transduction
  • Transforming Growth Factor beta / metabolism


  • Extracellular Matrix Proteins
  • Transforming Growth Factor beta
  • CILP protein, human
  • Pyrophosphatases

Associated data

  • OMIM/177170
  • OMIM/183900