Scientists Pinpoint Gene Behind Autoimmune Diseases

VAriations in it responsible for multitude of diseases, they say

By Amanda Gardner
HealthDay Reporter
Wednesday, March 21, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

WEDNESDAY, March 21 (HealthDay News) -- Variations in one specific gene appear to be behind several different autoimmune and auto-inflammatory diseases.

The pinpointed region of chromosome 17, called NALP1, could be a new target for treatment, said the authors of a study in the March 22 issue of the New England Journal of Medicine.

"This part of the immune system may respond to triggers coming from the environment, like bacteria or viruses, and there are indications that you can turn it off. So, we're very, very hopeful that there may be drugs that allow us to do that," said the study's senior author, Dr. Richard A. Spritz, who directs the Human Medical Genetics Program at the University of Colorado at Denver and Health Sciences Center.

Spritz added, "That's not going to help people with childhood diabetes, where the damage is already complete. But, for a number of chronic autoimmune disorders, like lupus and vitiligo, if you turn off the autoimmune process, the body could repair itself."

Some 80 autoimmune and auto-inflammatory disorders, which occur when the immune system malfunctions and starts destroying normal tissue, affect between 15 million and 25 million people in the United States, particularly women.

A few of the autoimmune diseases are caused by mutations in single genes, but most appear to be more complex. Scientists suspect that some genes may predispose individuals to one or more diseases, whereas other genes may predispose individuals to autoimmune and auto-inflammatory diseases in general.

"There has been a feeling for decades that autoimmune diseases are somehow related," said Dr. Peter Gregersen, author of an accompanying editorial in the journal and director of the Robert S. Boas Center for Genomics and Human Genetics at the Feinstein Institute for Medical Research in Manhasset, N.Y.

Interactions between gene variants and environmental factors also play a role in triggering the onset of a disease.

Spritz and his colleagues have long focused on patients with vitiligo, a disorder in which pigment cells are destroyed, resulting in white patches on the skin and sometimes the hair. Individuals with vitiligo tend also to have other autoimmune and auto-inflammatory diseases, as do their relatives. But the combinations of diseases are not very consistent.