New Batch of Lupus Genes Discovered

ByABC News
March 24, 2008, 2:44 AM

Mar. 23 -- MONDAY, Jan. 21 (HealthDay News) -- Researchers from around the world have pinpointed a batch of genes that can trigger lupus, a complex autoimmune disorder that has defied both a clear-cut diagnosis and a cure for decades.

"It's an important moment in autoimmune disease research," noted Dr. Noel Rose, who is director of the Johns Hopkins Center for Autoimmune Disease Research. At least 1.5 million people in the United States suffer from lupus, a disease in which the body mistakenly begins to attack itself.

The papers, three of which appear in the Jan. 20 online issue of Nature Medicine and one of which is published in the Jan. 20 online issue of the New England Journal of Medicine, identify both novel and familiar genetic suspects for lupus. The findings lend support to the theory that a "consortium" of genes are responsible for the development of lupus, said Rose, who three decades ago became one of the first researchers to connect a specific gene with an autoimmune disease.

The researchers identified several new genetic players -- ITGAM, KIAA1542, PXK and rs10798269 among them -- that raise the risk of developing lupus, and they also confirmed other genetic regions already associated with the disease. Some of the genes that had been identified previously, such as PTPN22 and STAT 4, are associated with other autoimmune diseases such a rheumatoid arthritis and type 1 diabetes, the researchers noted.

"It is exactly the thing I was dreaming about so many years ago -- that there would be common genes that would be involved in many autoimmune diseases," Rose said. It's a case of the "bad luck hypothesis," which means "you inherited all of these genes that are perfectly normal regulatory genes, and you got just too many of them, and that will bias your response this way or that way" in terms of developing the disease, Rose explained.

The discovery that many genes are involved "means we may be one step closer to better therapies in the short run -- several years as opposed to 10 years. If we can figure out what these genes are responsible for and we can alter that, we may have a major impact on the disease," said Dr. Susan Manzi, co-director of the Lupus Center for Excellence at the University of Pittsburgh and a co-author on one of the studies.