Scientists Reach Milestone in Defining Genetic Basis for Rheumatoid Arthritis

Rheumatoid arthritis (RA) can be painful to those who develop it. Now, scientists have discovered new genes, pathways and cell types that are involved in inherited susceptibility to RA. The findings could help researchers better aid those who are at risk for developing RA.

Rheumatoid arthritis is a long-term inflammatory disorder that may affect many tissues and organs. Principally, though, RA attacks flexible joints. It can be a disabling and painful condition and can lead to substantial loss of functioning and mobility if it's not adequately treated. In fact, the disease often leads to the destruction of cartilage and fusion of the joints. It can also produce inflammation in areas of the body that include the lungs, membrane around the heart and white of the eye.

In order to learn a bit more about this condition, the researchers performed a genome-wide association study (GWAS) meta-analysis in more than 100,000 people of European and Asian descent. In the end, they discovered 42 new sites of genetic variation involved n risk for RA. The analysis provided specific locations of genes, DNA sequences or positions on chromosomes for these genetic differences. This brought the catalog of confirmed risk variants for RA to over 100 genetic loci.

"This study is the culmination of over a decade of work by an extraordinary group of collaborative scientists from around the world," said Peter K. Gregersen, one of the researchers, in a news release. "It provides us with a definitive list of the major common genetic variation involved in this disease, and points the way forward to develop new diagnostic and therapeutic approaches to this illness."

The findings could help researchers develop new treatments in the future. In addition, it provides a compelling link between human genetics in RA and approved therapies to treat RA. The findings could also potentially be used to investigate therapies for other complex diseases such as lupus, diabetes and Alzheimer's disease.

The findings are published in the journal Nature.