WEDNESDAY, June 16 (HealthDay News) -- A new study finds that
rare gene variations are more common in people with disorders in
which the immune system attacks the body. These autoimmune
disorders include rheumatoid arthritis and type 1 diabetes.
Researchers report that the findings could lead to better
treatments -- although that's not guaranteed -- and pave the way
for scientists to link uncommon genetic variations to other
The research is focused on mutations in the gene coding an
enzyme in charge of a crucial cell in the immune system. The
enzyme, called sialic acid acetylesterase, controls the immune
system's B cells -- white cells that produce antibodies to fight
the foreign proteins of viruses, bacteria and other invaders. If
the enzyme fails to rein in the B cells, they may attack the body's
healthy cells by mistake.
The study authors compared the genetic makeup of 923 people with
common autoimmune disorders to a control group of 648 people
without them. They found a genetic variation that interferes with
the enzyme in 24 of the participants with autoimmune diseases but
just two of the controls.
The gene variant accounts for only about 2 or 3 percent of
autoimmune disease cases, but "we are actively investigating other
genes in this pathway that may be defective in a larger percentage
of patients," said study senior author Dr. Shiv Pillai, an
associate professor of medicine at Harvard Medical School and
researcher at the Massachusetts General Hospital Center for Cancer
Research, in a hospital news release.
The research appears online June 16 in the journal
Learn more about autoimmune disorders from the
U.S. National Library of Medicine.