Genetic Markers Spotted for Lupus

Nov. 10, 2006 -- New research on the genetic roots of lupus may eventually lead to a blood test to help diagnose the disease.

Lupus is an autoimmune disease in which the immune system mistakes the body's connective tissue for a foreign invader and attacks it.

The exact cause of lupus isn't known, but research suggests a mix of genetic and environmental influences.

Lupus can be hard to diagnose, since symptoms may mimic those of other diseases and can vary from patient to patient.

Researchers studying the genetics of lupus include Nilamadhab Mishra, MD, an assistant professor of rheumatology at Wake Forest University's medical school.

Mishra and colleagues have identified 40 genetic biomarkers of lupus. Those biomarkers are microRNAs -- tiny chains of ribonucleic acid (RNA) in a cell's command center (nucleus).

MicroRNAs are involved in cells' life, growth, and death; they can also help silence certain genes, Mishra's team notes.

The researchers compared microRNAs in blood cells of five lupus patients and seven people without lupus. The lupus patients had inactive disease and weren't taking prednisone or certain other drugs.

Participants' blood samples were taken twice over three months.

Forty microRNAs were present at higher levels in the lupus patients than those without lupus, the study shows.

MicroRNAs "may be useful as biomarkers in human lupus," the researchers write.

Their findings will be presented on Nov. 14 in Washington, D.C., at the annual meeting of the American College of Rheumatology and the Association of Rheumatology Health Professionals.

The results haven't yet led to the creation of a genetic blood test for lupus. But if the findings hold up in future studies, such tests might be possible.

SOURCES: Annual Meeting of the American College of Rheumatology and Association of Rheumatology Health Professionals, Washington, D.C., Nov. 10-15, 2006. WebMD Medical Reference: "Understanding Lupus -- the Basics." WebMD Medical Reference: "Understanding Lupus -- Treatment." News release, Wake Forest University Baptist Medical Center.