Humans are all almost exactly the same... almost - Greg Foot
Medical science has a problem—
it’s missing something.
Something that means
that not only is it harder to find
the causes of some diseases—
and effective ways to treat them—
some diseases are getting
overlooked entirely.
It turns out what it’s missing
could be you—
but I’ll get to that in a bit.
Because first, a story.
Or 8 billion stories, to be precise.
See, our DNA is our body's
instruction manual, sure.
But it’s also a history book that records
our own, unique genetic story.
All our stories begin
around 300,000 years ago
when humans arose in Africa.
Some genetic stories tell of leaving
a couple of hundred thousand years later,
journeying into Europe, East Asia,
or the Americas.
Some genetic stories
speak of expanding empires.
Others the diseases we evolved
to ward off,
and some the simple act of settling down,
raising cattle, and drinking their milk.
Each of our genetic stories are different,
but maybe not as different
as you might expect.
We share 99.9% of our DNA with each other.
Our stories are 99.9% identical,
but that 0.1% difference
is incredibly powerful.
In that tiny difference
between our genetic stories
is where we have the potential to develop
better treatments for diseases—
treatments that work for everyone.
But medical science isn’t currently
reading all those stories.
To explain let me tell you how researchers
work out the causes of diseases,
and develop and test the effectiveness
and safety of new treatments.
To find out the causes
of a particular disease,
researchers find lots of people
who have that condition
and comb through their genetic stories.
They look for little variations
they share—
little bits of their DNA stories
that are spelt differently.
If they find some, then they try all sorts
of different ways
of dealing with the effect of them.
And if that uncovers
something that looks promising,
they then run a clinical trial to see
if it actually is.
In phase one, a small group of volunteers
try the treatment.
Well, often only half of them do,
with the other half getting a placebo
that does absolutely nothing.
If there aren’t any notable side effects
at the target dose,
the treatment is cleared to move on
to the next stage of the clinical trial.
Phase two, this time with a bigger group
of participants
who all have the condition the researchers
hope the drug will treat.
If the drug appears effective,
it moves on to phase three,
with more participants trying
it for even longer.
Only after all this is the new treatment
then reviewed
and— hopefully— approved for use by us,
the general population.
But there's a problem with it.
Here is the ethnicity of lots and lots
of people used to recently find
the causes of various diseases.
And here is how that compares
to the ethnic diversity
of the world’s population.
Spot the difference?
The genetic stories that researchers are
combing through are heavily biased
to those of people from European descent.
Which means that if you’re searching
for those disease-causing bits of DNA
to target new drugs against,
and you're mainly reading the stories
of people of European descent,
you might completely overlook
key bits in the stories
of other diverse groups that tell of, say,
a changed risk of disease or even
shed light on how a disease occurs—
for example, scientists may not have
found the mutation
that causes sickle cell disorder
if we’d only looked in the stories
of people of European descent.
And the thing is, what medical science
is missing doesn't end there.
When new treatments or medical devices
are being tested,
they need to be tested on everyone
that may use them.
If the genetic stories involved
don’t reflect the breadth of stories
in our worldwide library then, again,
something might be missed.
Take, for example, the medicine Warfarin;
used to prevent blood clots.
Researchers have found that,
to produce the same effect,
most people of East Asian descent
need a lower dose
than some people of European descent,
and most people of African ethnicity
need a larger dose.
Which means the dose that works
best for someone
may vary according to their ethnicity.
It’s this kind of important information
that can be missed if clinical trials
don’t include people from across a range
of ethnicities.
So what’s the solution?
Well, it’s quite simple... in theory.
In order to develop treatments
that work better for everyone,
we need to involve everyone’s stories
in medical research—
in the early stage research,
in the drug development process,
and right through the clinical trial.
The good news is that more and more
people are thinking about this.
For example, cancer researchers
at University College London
researching genetic markers for cancer
want to analyze tissue samples
from a wide range of ethnicities so that
the biomarkers of cancer they identify
will be relevant for people from as many
ethnicities as possible.
Bottom line: medical science
needs to ensure
it’s got the best library it can have—
the one with the widest collection
of genetic stories possible,
so that everyone’s story
can be considered—
including yours.
That is the only way to ensure
everyone, everywhere
can get the best medical treatment
they possibly can.
