Genomic study of ossification of the posterior longitudinal ligament of the spine.

Ossification of the posterior longitudinal ligament of the spine (OPLL) is a common disease after the middle age. OPLL frequently causes serious neurological problems due to compression of the spinal cord and/or nerve roots. OPLL occurs in patients with monogenic metabolic diseases including rickets/osteomalacia and hypoparathyroidism; however most of OPLL is idiopathic and is considered as a multi-factorial (polygenic) disease influenced by genetic and environmental factors. Genomic studies for the genetic factors of OPLL have been conducted, mainly in Japan, including linkage and association studies. This paper reviews the recent progress in the genomic study of OPLL and comments on its future direction.