Intervertebral disc disease ... (Intervertebral disc disease)

The intervertebral disc disease is a common condition characterized by degeneration of one or more of the discs separating the vertebrae, causing pain in the back or neck and often in the legs and arms. Intervertebral discs provide cushioning between the vertebrae and absorb the pressure on the spine. Although the discs of the lower back are the most affected intervertebral disc disease, any part of the spine may have disc degeneration. Depending on the location of the disk or disks affected, this disease can cause periodic or chronic back pain or neck. Often the pain is more intense when sitting, bending, twisting and lifting.

Degenerated discs are prone to herniation; the protruding disc may press against one of the spinal nerves extend from the spinal cord to the rest of the body. This pressure causes pain, weakness and numbness in the back and legs. Often disc herniations cause sciatic nerve pain, extending from the lower back along each leg. Also, as a disc degenerates, you can form bone spurs on the edges of the affected vertebrae. These bone spurs can compress the spinal nerves, leading to weakness or numbness in the arms or legs. If bone spurs compress the spinal cord, affected individuals may have trouble walking, and problems in controlling bladder and bowel. Eventually, a disc degenerating can be broken completely and no space between the vertebrae, which can cause impaired movement, pain and nerve damage.

This process is due to a combination of genetic and environmental factors. Some of these factors have been identified, but many remain unknown. Variations have been identified in several genes that may influence the risk of developing the disease of the intervertebral disc. Genes involved more frequently in this process encode collagen synthesis which reinforce and support the connective tissues such as skin, bones, cartilage, tendons and ligaments. Collagens form a network of fibers that create the structure and stability within the intervertebral discs. Specific variations in several genes encoding collagen appear to affect the risk of developing the disease of the intervertebral disc by altering the ability of collagens interact with each other, decreasing the stability of the disc and causing their degeneration.

Normal variations in those related to the body 's immune function genes are also associated with an increased risk of developing the disease of the intervertebral disc. These genes play a role in triggering an immune response when the body detects a foreign invader such as a virus. It is believed that these genetic variants can elicit an immune response resulting in inflammation and dehydration of the disc, causing degeneration.

Also described variants in genes that play a role in the development and maintenance of intervertebral discs and the vertebrae associated with intervertebral disc disease. Associated variants may cause disc degeneration and herniation. It is working to identify and confirm other genetic changes associated with an increased risk of the disease. In addition, they are studying non - genetic factors that contribute to disease risk, such as age, smoking, obesity, chronic inflammation, and driving for long periods of time

Some of the identified genes associated with intervertebral disc disease include:

      • ACAN (aggrecan), 15q26.1.
      • ASPN (asporin) 9q22.31.
      • LRIC (intermediate layer protein cartilage), 15q22.31.
      • COL1A1 (collagen type I alpha 1 chain), 17q21.33.
      • COL9A2 (collagen type IX alpha 2 chain), 1p34.2.
      • COL9A3 (collagen type IX alpha 3 chain), 20q13.33.
      • COL11A1 (collagen type XI alpha 1 chain), 1p21.1.
      • IGF1R (Insulin like growth factor 1 receptor), 15q26.3.
      • IL1A (interleukin 1 alpha), 2q14.1.
      • MMP2 (matrix metallopeptidase 2), 16q12.2.
      • MMP9 (matrix metallopeptidase 9), 20q13.12.
      • THBS2 (thrombospondin 2), 6q27.
      • VDR (vitamin D (1,25- dihydroxyvitamin D3) receptor), 12q13.11.

The intervertebral disc disease can be inherited, but the pattern of inheritance is generally unknown. People with first - degree relative with intervertebral disc disease have a higher risk of developing the condition. People can inherit a genetic variation that increases the risk of disease of the intervertebral disc, but do not inherit the disease itself. Not all people with spinal disc disease have a variation in one of the identified genes that increase the risk, and not all people with a variation of these genes will develop the disease.  

Tests performed in IVAMI: in IVAMI perform the detection of mutations associated with intervertebral disc disease by the complete PCR amplification of the exons of ACAN, ASPN, CILP, COL1A1, COL9A2, COL9A3, COL11A1, IGF1R, IL1A gene, MMP2, MMP9, THBS2 and VDR, respectively, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).