Case Study
RETT SYNDROME: HOPE OF CURE DRIVES
FUNDRAISING AND UNDERPINS NEW TRIALS
SYMPTOMS SHOWN TO
BE REVERSIBLE IN MICE
Rett syndrome affects one in 10,000 girls.
Rett syndrome is a severe autistic-spectrum disorder with
delayed onset that affects 1 in 10,000 girls. Some 16,000
individuals have Rett syndrome in the US, and an estimated
2,400 in the UK. It is a regressive disease that causes loss of
speech and hand movement, coupled with autistic behaviour,
an undersized brain (microencephaly), and growth retardation.
Affected girls develop normally for around 18 months then
regress, losing abilities they once had and requiring increasing
levels of care as they age.
In 2007, Dr Jacky Guy and other scientists in
Professor Sir Adrian Bird’s group introduced
a modified MeCP2 gene into Rett model
mice that allowed controlled expression of
normal MeCP2 protein. Mutant female mice
carrying this modified gene exhibited the
characteristics of Rett syndrome until normal
MeCP2 expression was activated, after which
they rapidly regained normal behaviour.
This striking result indicated that the
developmental or degenerative changes seen
in Rett patients are reversible, and overturned
previous understanding of the disease.
Rett syndrome was previously believed to be a developmental
or neurodegenerative disease because of its early appearance
and the gradual deterioration of those affected. A cure or
therapy was thought to be most unlikely.
In most cases the disease is due to mutations in the
gene coding for MeCP2, which negatively regulates gene
expression. In 2001, researchers led by Professor Sir
Adrian Bird developed a mouse model for Rett syndrome
by introducing a mutation into the mouse MeCP2 gene.
Heterozygous female mice carrying this mutation had
behavioural characteristics similar to those of girls with Rett
syndrome, including poor motor coordination, behavioural
deficits and breathing arrhythmia. This mouse model is
currently used in hundreds of labs across the world.
A scientist in Professor Sir Adrian
Bird’s research group at work. CHARITY FORMATION AND
INCREASED AWARENESS
RESEARCH FINDINGS
UNDERPIN CLINICAL TRIALS
Multiple clinical trials are under way in
both Europe and the US to test a variety
of drugs in the hope of achieving symptom
improvement. For example, a trial of Insulinlike Growth Factor-1 (IGF-1) is in progress.
IGF-1 is indirectly regulated by MeCP2
and has been shown to ameliorate several
features of Rett-like disease in mice. The
Edinburgh research underpins the rationale
of the trial.
The RSRT public information campaign in Times Square, New York.
As a direct result of the 2007 results, a small group of US
parents of children with Rett syndrome, led by Monica
Coenraads, formed the Rett Syndrome Research Trust (RSRT),
a highly efficient non-profit charity devoted to finding a cure
for the condition. The RSRT was established purely because
these parents believed there was now a real prospect of a cure
for Rett syndrome. The RSRT was launched in September
2008 and has so far raised more than $25 million in donations.
A remarkable 96 per cent of funding raised is committed to
research seeking to cure Rett Syndrome.
The RSRT launched a powerful campaign in November
2011 to boost awareness of Rett syndrome. It is estimated
that 1.5 million people per day for three months viewed the
campaign’s public service announcement in Times Square,
New York. In addition, the documentary film RETT: there is
hope, was honoured in 2012 with a Rising Star Award (Canada
International Film Festival) and won the USA Awareness Film
Festival. Filmmaker Jason Rem was inspired to make the
documentary, which features the Edinburgh research, after
attending an RSRT charity event.
The UK charity ReverseRett was formed in July 2010 by
families across the UK who wanted to contribute to RSRT’s
efforts to accelerate treatments for Rett Syndrome. The UK
charity has raised £2 million since 2010.
Rachael Bloom, Executive Director of ReverseRett, says:
‘This is a global issue not a national issue. In every country,
children with Rett syndrome are suffering tremendously. This
relentless disorder impacts children and the families who love
them across all cultures and races. We believe Rett syndrome
is reversible. Everything we do stems from this belief.’
Concurrently, research targeted at the
underlying cause of Rett Syndrome, for
example gene therapy with MeCP2, is
being pursued. It is expected that attacking
the root of the problem in this debilitating
disease may profoundly impact symptoms.