26 September 2020 | New Scientist | 39TI >
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N 1990, an international group
of scientists embarked on one of the
most ambitious research projects ever
undertaken. They would sequence the
entire human genome, determining
the order of the 3.3 billion base pairs
that code for the genes that make the
proteins that each of us are built from.
There was huge excitement at the prospect
of decoding the “blueprint” of humanity.
Given the complexity of our species, our
genome was expected to contain at least
100,000 genes. What makes us human
would finally be laid bare.
It didn’t quite work out like that.
The Human Genome Project was a
resounding success, publishing its
results in 2003, two years ahead of target.
However, it revealed that humans only
have around 22,000 genes, which is
about the same number as other
mammals. Meanwhile, the blueprint
itself turned out to be encrypted in
ways we are still trying to crack.
The same thing is true of us that is
true of every species: our DNA can be
expressed in myriad different ways
depending on which combination of
sequences is activated. It is this, not theGENES AREN’T DESTINY
The principle of genetic plasticity