Gene Linked to Blood Vessel Breakdown Identified

by VR Sreeraman on Jul 30 2007 6:33 PM

Scientists have linked blood vessel breakdown, a fatal genetic disorder, to mutations in a gene known as TREX1.

The recent discovery will help understand retinal vasculopathy with cerebral leukodystrophy (RVCL), which was discovered twenty-one years ago.

RVCL is a complex and ultimately fatal barrage of primarily central nervous system with symptoms like vision loss; mini-strokes and dementia can become fatal in ten years or less.

"Why TREX1 mutations would suddenly cause these blood vessels to start disappearing at midlife is a mystery. But now that we have this link, what it teaches us about the health and maintenance of these blood vessels also may help a great deal in understanding and preventing their loss in aging and in diabetes," Nature Genetics quoted says senior author John Atkinson, M.D., the Samuel Grant Professor of Medicine and professor of molecular microbiology, as saying.

Other disorders linked to blood vessel loss are vascular dementia, which leads to memory loss, disorientation, and emotional problems in elders.

Since the discovery of the condition in 1986, researchers have unveiled several other families with RVCL in Europe, Australia and Taiwan.

A small but rapidly expanding body of scientific literature already exists on TREX1, which is an important mammalian gene. It is active in almost all cells, where it proofreads DNA for errors and helps correct those mistakes. Cells sometimes introduce such errors into DNA when they copy it prior to cell division, and environmental factors like radiation and reactive chemicals can also create errors.

According to Atkinson, there isn't much information on why TREX1 causes small blood vessels to start dying off in middle-aged RVCL patients.

"We're going to be working very hard to understand everything we can about TREX1 to try to give us some hints about what's happening to people with RVCL and how we can help," Atkinson said

"What we learn may provide insights into why these same vessels sometimes start to die off in the elderly, leading to a variety of complications. The disease was discovered here in St. Louis, its genetic basis was identified by the GSC, and now our goal is to find a treatment,' he added.

The current study has identified in RVCL patients create a tailless form of the TREX1 protein that can't properly attach itself to the portion of the cell that it attacks. Researchers are trying to find whether this displacement could have any links to the damage that occurs in RVCL.