Toronto, Feb 3 (IANS): Researchers have identified for the first time a gene that causes idiopathic scoliosis, a type of spinal deformity.

The gene POC5 is responsible for idiopathic scoliosis in families of French origin, the findings showed.

"Mystery surrounds the cause of scoliosis, which is a three dimensional deformation of the vertebral column," said lead author Florina Moldovan from University of Montreal in Canada.

"To date, many genes have been suspected of causing scoliosis amongst different populations, but the gene that causes the familial form of the disease remained unknown," Moldovan said.

"This is a very heterogenous disease and probably more than one gene is required for disease expression. This discovery has enabled the identification of the first causative gene and represents an important step towards decoding its genetic causes," Moldovan said.

A variation in the POC5 gene was initially identified by DNA sequencing in the samples the researchers collected from a large French family, of whom several members are affected by idiopathic scoliosis.

Others variants of the POC5 gene were detected in scoliotic families and in people whose scoliosis had no precedence in their families.

"The pathogenicity of POC5 variants was documented by using the zebrafish, a well-established genetic animal model that has a spine," first author Shunmoogum (Kessen) Patten from CHU Sainte-Justine, a research centre in Canada.

This model revealed that the over-expression of mutated human POC5 gene led to the rotational deformation of the anterior-posterior axis of the spine in half of the zebrafish embryos.

The deformations are similar to the deformations observed in scoliosis patients, the researchers noted.

The study appeared in the Journal of Clinical Investigation.