Scientists have long known that the autoimmune disease lupus disproportionately strikes women. And though they have searched for a genetic link between the disease and the X chromosome—women carry two, while men carry only one—they’ve not found one.
Oklahoma Medical Research Foundation scientist Amr Sawalha, M.D., has discovered an association between a gene located on the X chromosome and the risk of developing lupus. This gene, known as MECP2, plays a critical role in regulating the production of many genes.
The discovery could, in the long term, lead to new therapies for the disease, which affects as many as 2 million Americans and 15 million people worldwide. Sawalha, who also serves as an assistant professor of medicine at the University of Oklahoma Health Sciences Center and a staff physician with the Veteran’s Administration Hospital in Oklahoma City, detailed his findings in a paper published today in the online scientific journal PLOS One.
Lupus is a chronic, relapsing autoimmune disease in which a person’s over-productive immune system begins attacking the body instead of fighting infections and disease. Lupus can affect any part of the body and can be life-threatening. The disease, which has no known cure, occurs in about 31 out of every 100,000 people and affects women nine times more frequently than men.
“It’s a debilitating disease that can affect multiple organs, the kidneys, the nervous system, the lungs, the heart, the joints and the skin,” said Sawalha. “Right now, the only treatment we have is immunosuppressive drugs.”
The problem, Sawalha said, is that current treatments only fight the symptoms and manifestations of lupus, not the cause of the disease itself. “Over time, the drugs are toxic, and the side effects can be serious,” he said.
Sawalha said the immediate upshot of the discovery will be a better understanding of the cause of lupus. Further research will involve comparing cell lines from lupus patients with and without the abnormal gene, he said. He also will focus on finding “downstream targets”—other genes that are affected by the genetic abnormality discovered.
“In the long-term, we hope these findings will help lead to new lupus therapies,” said Sawalha.
The research was supported by the National Institutes of Health, the Oklahoma Medical Research Foundation, the University of Oklahoma College of Medicine, the U.S. Department of Veterans Affairs, a Kirkland Scholar Award and the Alliance for Lupus Research.
Lupus occurs when the body confuses pieces of itself for foreign invaders like germs. It most commonly strikes the skin, joints, blood and kidneys, although it can attack any part of the body. The disease, which can be fatal, affects as many as 2 million Americans and 15 million people worldwide.
OMRF (omrf.org) is an independent, nonprofit biomedical research institute dedicated to understanding and developing more effective treatments for human disease. Chartered in 1946, its scientists focus on such critical research areas as Alzheimer’s disease, cancer, lupus and cardiovascular disease.