were resilient to a selection of eight
genetic conditions.
Three were resistant to cystic
fibrosis, a serious disease affecting
the lungs and other organs.
Another three were unaffected by
gene faults that should have caused
major bone abnormalities, known as
atelosteogenesis. Two were immune
to the impact of mutations in a gene
called DHCR7, usually responsible
for a severe developmental disorder
known as Smith-Lemli-Opitz
syndrome. Another five had their own
unique genetic superpowers against a
selection of brain, bone, skin and auto-
immune diseases.Holding out for a hero
Frustratingly, the identities of these
masked men and women will remain
a mystery. Due to anonymisation
and lack of the right consent to re-
contact the people in the databases,
the Resilience Project wasn’t able to
track any of them down for further
investigation. This problem has led
to some criticisms of the study: there’s
still a chance that there may have beenShould I worry?
As well as rare disease-
causing mutations, we each
have thousands of minor
genetic changes – known as
variations – that have lesser
effects on our bodies, brains
and health.What is DNA?
DNA is the genetic instruction
manual in our cells. Genes
are stretches of DNA that
act as ‘recipes’ for making
molecules called proteins,
which build our bodies
and keep them working.What is a mutation?
Changes in genes (mutations)
can affect the protein they
encode, making it more or
less active, or causing
disease. For example, if you
have a mutation in the gene
BRCA2 (pictured), you have a
higher risk of breast cancer.How do mutations
happen?
Mutations can be inherited
or can occur when eggs
and sperm are made, or in
the fertilised egg (pictured left).Can adults get mutations?
Mutations can occur in the DNA
within cells in the adult body.
While these changes can’t be
passed on to the next gener-
ation, they can lead to diseases.
For example, smoking damages
DNA, which can cause lung
cancer (pictured).identity mix-ups along the way (not
unusual in such large-scale projects)
or that they do actually have mild or
even more severe forms of the
conditions they appear to have evaded.
There may be other issues too.
The biggest is the mutation database
itself. This is the resource that lists all
the genetic faults known to be linked
to diseases. This makes Wijmenga
sceptical about the powers of many of
the individuals she found in her study.
“All of them are disease genes, but
some of them are really common in the
Dutch population, and that makes you
wonder if those are true mutations or
they just ended up in the database in
the past but don’t actually cause
disease,” she says. “For some of these
variants, around 90 per cent of the
people have the mutant version,
which doesn’t make sense if it’s a real
mutation. These things should be rare.
So this tells us that the databases aren’t
that good.”
That said, there’s still evidence
that some superheroes, at least in the
genetic sense, are real. And although
the identities of those in the ResilienceCystic fibrosis is caused
when a child inherits the faulty
mutation (red) from both their
mum and their dad.80 February 2017| GENETICSSCIENCEGENES AND MUTATIONS:
A QUICK REFRESHER
74 February 2017