research
Why me? Searching for answers
‘Why me?’ is a very natural response to a diagnosis of MND. Most people at
some point will wonder if a particular past experience or activity was the
cause of their disease, and this was the most common subject of queries
received by the Association’s Research Development Team last year. But
what does cause MND and how are we striving to find the answers? Kelly
Johnstone from our Research Development Team explains.
The study of lifestyle and
environmental factors in relation to
disease is known as epidemiology.
We often hear from people with MND
who ask us why the Association can’t
just do a big survey of everyone with
the disease that we’re in contact with
to find out the causes of MND. This
may seem like an ideal solution, but
unfortunately it is shrouded in pitfalls.
Really good epidemiological
research is not only expensive; it’s
actually extremely difficult to do and
requires a high level of expertise
in order to get good,
“In a tower, there
meaningful results.
To get reliable results, the
are always some
research needs to be very
blocks that are a
carefully designed with lots
little loose and an of controls and checks in
easy target for the place. This is why a general
survey is unlikely to tell us
players. ”
anything meaningful.
This is not to say
that these sorts of studies are not
important. Studies to date have given
us a lot of clues as to what may cause
MND.
“MND is a complex disease,” says
Dr Brian Dickie, our Director of
Research Development. “Unravelling
the tangled knot of environmental
and inherited factors that may lead to
I
f MND had just one cause, we’d have
found it a long time ago. Finding
the answer to what causes MND is
difficult because so many factors have
to come together to cause MND –
including environmental, lifestyle and
genetic factors.
This interplay works through
our different ‘spellings’ of genes
and the susceptibility they have to
environmental and lifestyle factors.
We can think of this as a game like
Jenga – a tumbling tower of blocks.
The tower itself is a person’s motor
nervous system, the wooden blocks
are the genes, and the players are
different risk factors.
In a tower, there are always
some blocks that are a little
loose and an easy target
for the players. The loose
blocks can be likened to
genes that are ‘spelled’ in
such a way that means the
nervous system is less able
to cope with certain environmental
factors that it encounters. When that
environmental factor plays our tower
game, it pokes out a loose block and
weakens the tower very slightly – but
it remains standing and there is no
MND as yet.
As time goes on, more and
more loose blocks are removed by
environmental and lifestyle factors
until eventually the tower collapses
and the nervous system succumbs to
MND. Each person is different, with
different risk factors involved and
different susceptibility genes that are
vulnerable.
Among healthy individuals there
will be some people with very few
susceptible (or ‘loose’) genes, whose
nervous system can cope with almost
anything that’s thrown at it. Others
may be genetically vulnerable but
never encounter enough risk factors
to weaken their nervous system to
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Finding the ‘big’ picture
the point of ‘tower collapse’. Due to
this subtle interplay between lifestyle,
environmental and genetic factors,
finding risk factors for MND is extremely
complicated.
Inherited MND
In five to ten percent of cases of MND,
the disease is known to be inherited.
The cause of MND for these cases is
known to lie within their genes. This
means that the tower starts with a few
blocks already removed. However, it
is still necessary for environmental
and lifestyle factors to combine
throughout the person’s life to
trigger the disease.
the development of the disease is no
easy process. Epidemiology plays an
important role in this process, helping
to generate new theories as to the
causes of MND and further studies
that can be tested in the laboratory.”
When history doesn’t
repeat itself…
Despite a huge amount of work, all
we really know so far is that MND is
more likely to occur as people get
older and is slightly more likely to
occur in men. Both of these findings
were verified in an MND Associationfunded epidemiology study in the
1990s based at Brunel University.
More recently, smoking has also been
confirmed as a small risk factor.
The way that we know if a study’s
results can be taken as ‘true’, is if
the findings are replicated by other
groups. Unfortunately, for every study
that has claimed to have found a
new risk factor, another is published
which contradicts it. This is why it is
important that future epidemiology
research is carefully planned and is of
the highest calibre.
How we’re finding the
answers
We are committed to finding the
causes of MND and are funding highquality research in a number of key
areas of scientific investigation which
may reveal the underlying causes
of MND and ultimately signpost to
possible treatments. These include
using cutting-edge techniques to
investigate why motor neurones
die; identifying potential disease
markers; discovering new causative
genes; and creating new models
of MND in the lab using stem cell
technology to rapidly test potential
new drugs. In addition, we also
Dr Brian Dickie,
our Director
of Research
Development
fund clinic-based research to try to
identify a commonality of people’s
life experiences through carefully
designed studies.
One ground-breaking project that
we are funding in this area is the
MND Association’s DNA Bank and
Epidemiology Study. This involves
selected participants at centres in
London, Birmingham and Sheffield
donating a DNA sample and
completing detailed and carefully
designed questionnaires.
Prof Ammar Al-Chalabi, based at
King’s College
London, is one
“Although our genes
of the principle
contain the recipe
investigators of
for making our bodies
this study:
“Although our
function, it is what we
genes contain
are exposed to in our
the recipe for
lives that is the cook.”
making our
bodies function,
it is what we are exposed to in our
lives that is the ‘cook’. By coupling our
growing understanding of genetics
with people’s life experiences in our
epidemiology study, we will begin
to understand how the two work
together to cause MND.”
Our online forum
The MND Association’s online forum
provides a safe place for people
affected by MND to share experiences
and support each other with the
challenges of living with the disease.
Robyn Copley-Hirst, in our MND
Connect team, co-ordinates the
forum: “Our forum is a great platform
for people affected by MND to talk
about matters that are important
to them. One recent discussion was
entitled ‘What do you think caused
your MND?’ and centred around
people’s own thoughts as to what
they feel caused their MND. Our forum
community has shared experiences
and incidents with each other from
car accidents, working with chemicals,
sporting injuries or some even sharing
that they can’t recollect anything
significant at all. The enthusiasm of
our forum community, to share their
experiences over a vast array of topics
from care to research issues, really
gives our forum a dynamic edge that
drives discussions, provides support
and forges new friendships.”
Visit our online forum:
http://forum.mndassociation.org
More information on epidemiology:
Visit: www.mndassociation.org/causes
Read our blog: mndresearch.
wordpress.com
Follow us on twitter @mndresearch
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