Systemic lupus is a chronic inflammatory disease that can involve many organs, and often strikes the joints, kidneys, heart, lungs brain and the blood.

The interaction of genetic variants and environmental factors are thought to contribute lupus susceptibility and severity, so the variants are a diagnostic tool and not a confirmation of disease. Lupus affects between 1 million and 2 million Americans, mostly women.

Currently there is no cure for lupus, but early diagnosis and proper medical treatment can significantly reduce inflammation, pain and stop future complications.

In 2005 the Alliance for Lupus Research (ALR) formed and supported the International Systemic Lupus Erythematosus Genetics  (SLEGEN) Consortium, charging scientists with searching for genetic variants that might predispose an individual to developing lupus.

In the past there years, the researchers studied the DNA of more than 6,700 women, including individuals with lupus, their family members and control subjects. Their goal was to identify single nucleotide polymorphisms (SNPs) linked to lupus. SNPs are locations on chromosomes where a single unit of DNA, or genetic material, may vary from one person to the next.

SLEGEN Director John B. Harley, M.D., Ph.D., explained that the study found strong evidence of association with multiple single nucleotide polymorphisms (SNPs) in three genes: ITGAM; KIAA1542; PXK; and at SNP rs10798269, a DNA unit not found within any known gene.

ITGAM is important for both the adherence of immune cells and for cleaning up pathogens, while KIAA1542 is important for translating the DNA code into proteins. The results also showed evidence linking lupus to nine other genes.

“This initial, important discovery will prove invaluable to all those affected by lupus,” said Barbara Boyts, president of the Alliance for Lupus Research. “We are hopeful that this information will lead to new and better treatment possibilities and, eventually, a cure for lupus.”

The scientists are now focusing their attention on specific pathways and genes, trying to dissect the precise molecular mechanisms by which these genes contribute to the risk for lupus. Genetic factors likely predict specific complications or patterns of complications.

“These findings underscore that numerous genes, which are often immune-function related, contribute to the risk of developing lupus,” said Carl D. Langefeld, Ph.D., senior author from Wake Forest University School of Medicine and co-director of SLEGEN.

“These results suggest biologic pathways that help us understand the condition better and suggest additional genetic and non-genetic triggers,” said Langefeld.