
New gene test detects fatal
copper disorder
A test developed by scientists
in the US could greatly extend
the survival of infants with
Menkes disease, a rare, otherwise
fatal disorder of copper
metabolism. The scientists
devised a test to diagnose the
condition early, when the
chances for successful treatment
are greatest. A study
appears in the 7 February 2008
New England Journal of
Medicine.
Untreated, Menkes disease
results in irreparable harm to
the brain and nervous system.
Treatment consists of injections
with a copper-containing
drug. Children with Menkes
disease typically die during the
first decade of life. Previously,
there was no blood test for
early detection of Menkes
disease.
“The study represents an
important advance in the
diagnosis and treatment of a
rare but devastating genetic
disorder,” said Duane
Alexander, MD, director of
the US National Institute of
Child Health and Human
Development (NICHD),
which lead the study. “The
laboratory techniques the
researchers used to detect
Menkes disease eventually
may provide the basis for a
newborn screening test to
identify children with Menkes
at birth, so they have the
greatest chance to benefit
from treatment.”
Stephen G. Kaler, MD clinical
director of the NICHD
and lead author of the study
said the defect, in the gene
designated ATP7A, causes
abnormally low levels of
copper in the brain and liver as
well as excessive amounts of
copper in the kidneys and
intestines. Copper, although
only needed in trace amounts,
is an essential nutrient that
plays a critical role in brain
development.
Infants with Menkes disease
usually appear normal at birth
but start to show developmental
delays at 6 to 8 weeks.
Affected children may experience
seizures and below normal
body temperature. Children
with Menkes disease also
develop distinctive kinky hair,
which is steel-colored or
colourless and is easily rubbed
off the skull.
Dr Kaler explained that
copper is needed for the
production of myelin, an insulating
material that surrounds
certain types of brain and nerve
cells. The deposition of myelin
around brain and nerve cells is
nearly completed by age 2, so
the disorder can potentially be
treated if copper replacement
therapy is started soon after
birth. Symptoms of Menkes
disease do not usually develop
until 2 to 3 months of age, but
by that time, the copper deficiency
has already caused significant
brain damage which treatment
seems unable to reverse,
Dr Kaler said.
The defective gene in Menkes disease is located on
the X chromosome. Because
males have only one X chromosome,
they have only one copy
of the ATP7A gene and so are
severely affected by the
disorder. Females have two X
chromosomes. If they have a
defective ATP7A gene, they are
not severely affected, because
their remaining X chromosome
usually has a functioning
ATP7A gene.

New research into scar-free healing
New research from the
University of Bristol shows
that by suppressing one of the
genes that normally switches
on in wound cells, wounds can
heal faster and reduce scarring.
This has major implications
not just for wound victims but
also for people who suffer
organ tissue damage through
illness or abdominal surgery.
Tissue damage triggers an
inflammatory response by white
cells to protect skin from infection
by killing microbes. The
same white cells guide the
production of layers of collagen.
These layers of collagen help
the wound heal but they stand
out from the surrounding skin
and result in scarring. Research
by Professor Paul Martin and
colleagues at the University of
Bristol shows that osteopontin
(OPN) is one of the genes that
triggers scarring and that
applying a gel, which suppresses
OPN to the wound, can accelerate
healing and reduces scarring.
It does this in part by
increasing the regeneration of
blood vessels around the wound
and speeding up tissue reconstruction.
The findings are published
by the Journal of Experimental
Medicine on 26 January 29\008
in a paper entitled ‘Molecular
mechanisms linking wound
inflammation and fibrosis:
knockdown of osteopontin
leads to rapid repair and
reduced scarring’.

Genetic basis for itchy skin
disorder discovered
A breakthrough study, funded
by UK charity Action Medical
Research, has found new
genetic mutations that can
cause the skin to itch.
Published 10 January 2008
in the American Journal of
Human Genetics the research
points to a genetic disorder
that directly causes itchy skin.
It is the first time a genetic
basis has been discovered for
itchy skin.
Hundreds of thousands of
sufferers around the world
suffer from an itchy skin
disorder known as primary localised cutaneous amyloidosis
(PLCA).
A multinational team of
dermatologists looked at the
inherited form of the disease
known as familial primary
cutaneous amyloidosis.
The research has shown that
mutations in the oncostatin M
receptor-beta gene (OSMR)
are the cause of this form of the
skin disorder.
The team has discovered
that skin cells with a mutant
copy of the OSMR gene
respond differently to certain
stimulating molecules known
as cytokines.
When stimulated with the
cytokines oncostatin M or
interleukin-31, the mutant
skin cells fail to activate a
number of anti-inflammatory
genes and the result is itchy
skin.
Professor McGrath, who is
also President of the European
Society for Dermatological
Research added, “This work
provides new insight into what
can cause itchy skin.
“We now plan to look for
abnormalities of this signalling
pathway in other itchy skin
disorders and, most importantly,
to examine how we can
develop new treatments for
that most common of all skin
symptoms, itch.”
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