Sydney: In a breakthrough that could pave the way for better treatment of patients suffering from a painful form of arthritis, which fuses bones in the spine and pelvis, scientists have isolated a group of genes causing the disease.

Researchers at the University of Queensland's Diamantina Institute (UQDI) have identified eight new genes that help clarify previously unexplained aspects of ankylosing spondylitis, reports the journal Nature Genetics, quoting an university release

Headed by Prof Matt Brown, the university's researchers formed an international consortium with research groups in Britain, US and Canada to embark upon the largest study in history into the genetic causes of AS.

The discovery in the understanding of molecular mechanisms underlying the disease will help explain why bone formation occurs and why some some of the patients also develop psoriasis or inflammatory bowel disease.

Ankylosing spondylitis causes the immune system to attack the spinal and pelvic joints, leading to chronic inflammation.

Unlike other forms of arthritis where inflammation leads to bone loss, this disease results in bone growth and can consequently cause the spine and/or pelvis to become fused into a fixed position. Currently there is no treatment available.

"These crucial findings provide the first confirmation that in humans, as has been shown in plant and other animal species, interaction between genes is important in influencing disease risk," Brown said.