Underlying Genetics
Researchers in Sweden found a common risk factor for not only MS,
but also ailments like heart disease and rheumatism. This risk
factor is a the gene that links autoimmune diseases like MS to
cardiovascular diseases, the first time such a gene has been
identified, say the scientists.

Experts on all three diseases collaborated to reach the findings.
Their study is published in the May 2005 issue of the journal
Nature Genetics.

"This gene variant can be one of the single largest genetic
causes of complex diseases with inflammatory components," said
Fredrik Piehl, MD, PhD, an associate professor in the department
of Clinical Neuroscience at the Karolinska Institutet in
Stockholm, who headed the study. "The discovery can now lead to
more reliable diagnostics and better treatments for a great
number of patients."

Culprit—Immune System Gone Awry?
Multiple sclerosis is the most common neurological disorder
diagnosed in young adults. Its causes are not yet fully
understood, but it is thought to be an autoimmune disease. The
disease affects the brain and spinal cord by damaging or
destroying a kind of protective insulation that covers nerves
known as myelin (MYE-uh-lin). The nerves themselves can also be
damaged at the onset of MS. As a result, messages from the
central nervous system to the rest of the body may short circuit,
causing reduced or lost body functions. Symptoms, however, vary
individual-to-individual. These include fatigue, visual
disorders, numbness, dizziness, bladder and bowel dysfunction,
weakness, tremor, impaired mobility, sexual dysfunction, slurred
speech, and spasticity.2

The origins of the disease are believed to lie in an abnormality
of the immune system, in which white blood cells—normally charged
to fight off infection or disease—are instead guided to target
and attack the body's own cells. This causes inflammation in the
brain and spinal cord which, in turn, can cause the injury
described above.2

Digging for Genetic Clues
For their analysis, Piehl and his colleagues first identified the
abnormal gene in an animal model, and then later studied this
gene in a number of patient groups to determine if it was linked
to any diseases found in humans. Piehl's group learned that those
with the gene variant faced up to a 40% greater risk of
developing multiple sclerosis, rheumatism, or myocardial
infarction—the medical term for heart attack.

They also discovered that the gene variant is relatively common
in people, affecting up to 25 percent of the general population.

Statin Connection?
This discovery, they say, has implications for
statins—anti-cholesterol medications that may be effective
against multiple sclerosis. The drugs work by easing the
inflammatory effects of MS. They do that by reducing the activity
of the gene variant discovered in this study, experts contend.3-5

As a result of this knowledge, clinical trials of statins as a
therapy for MS have been published in recent years, as well as
animal studies of the effectiveness of statins against an MS-like
disease.6-8

"There is a chance that other diseases are also affected by this
gene variant," Piehl explained.

For instance, the gene variant has shown it can reduce the
production of a number of immune defense proteins, and some
viruses and bacteria have shown they can influence the gene in an
attempt to evade immune system attacks as they mount an infection
in the body.9

1. Swanberg M, Lidman O, Padyukov L et al. MHC2TA is associated
with differential MHC molecule expression and susceptibility to
rheumatoid arthritis, multiple sclerosis, and myocardial
infarction. Nat Genet 2005 May;37(5):486-94. Epub 2005 Apr 10.
2. Multiple Sclerosis Society of America. What is Multiple
Sclerosis. Available at:
http://www.msaa.com/publications/allaboutms/p_01_whatis.html.
Accessed June 3, 2005.
3. Steffens S, Mach F. Anti-inflammatory properties of statins.
Semin Vasc Med 2004 Nov;4(4):417-22.
4. Crisby M. Modulation of the inflammatory process by statins.
Timely Top Med Cardiovasc Dis 2005 Mar 1;9:E3.
5. Okazaki H, Nagashima T, Minota S. Immunomodulatory activities
of statins. [Translated form Japanese]. Nihon Rinsho Meneki
Gakkai Kaishi 2004 Dec;27(6):357-60.
6. Vollmer T, Key L, Durkalski V et al. Oral simvastatin in
relapsing-remitting multiple sclerosis. Lancet 2004 May
15;363(9421):1607-8.
7. Mach F. Toward a role for statins in immunomodulation. Mol
Interv 2002 Dec;2(8):478-80.
8. Youssef S, Stuve O, Patarroyo JC et al. The HMG-CoA reductase
inhbitor, atorvastatin, promotes a Th2 bias and reverses
paralysis in central nervous system autoimmune disease. Nature
2002 Nov 7;420(6911):78-84.
9. Hiasa Y, Takahashi H, Shimizu M et al. Major
histocompatibility complex class-I presentation impaired in
transgenic mice expressing hepatitis C virus structural proteins
during dendritic cell maturation. J Med Virol 2004
Oct;74(2):253-61.

John Martin is a long-time health journalist and an editor for
Priority Healthcare. His credits include overseeing health news
coverage for the website of Fox Television's The Health Network,
and articles for the New York Post and other consumer and trade
publications.
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My ability .. in .. the courtroom .. surpasses my
ability .. in medicine ..
Tom Hennessy (thennessy@telus.net)
Message-ID: <l49da.24792$Ty5.1981914@news0.telusplanet.net>