Session page (no audio): https://schedule.sxsw.com/2018/events/PP80525
Jamie Metzl, Atlantic Council
The biggest revolution of our century is not the tech
revolution, it’s the biotech revolution, and specifically the genetics/genomics
revolution, all the biological connected systems that are going to change in a fundamental
way. After 3.8 Billion years of
Evolution by Darwinian principles of random mutation and natural selection, we
are turning a corner in Evolution towards a future where we are directing our
own evolutionary path.
With all the advances of mapping, sequencing and precision editing
the genom, we are beginning to hack the building blocks of life. The fundamental change of biogenetic
evolution is that we will realize our own genetic code is just another form of
information technology.
When we see science fiction, we see so many advances in
technology, but the people look just like we do now; but biology will not be
constant. If we had a time machine, and
went back 1000 years in the past, and brought a baby back, it would grow up to
be a regular human. But if we took a
baby from 1000 years in the future, it would grow up as a super-human among us –
live longer, healthier, have special capabilities and traits we don’t see
anywhere else. This will take time to
reach, but our improvements and the trajectory of change is increasing in
exponential speed. Among many things, this will change how long we live and how
well we live our lives.
The search for
longevity has driven a lot of the stories, myths and religions. Gilgamesh looks for immortality, Methuselah lives to 969
years old; the Chinese have myths of a mushroom that gives immortality, and
many other cultures were preoccupied with long life and immortality.
At the time of the Roman empire, average lifespan was 25; in
1900, average lifespan in the US was only 47 – 20 years increase over the span
of several millennia. But starting in
the 19th century, rate started to increase dramatically as a result
of better sanitation, nutrition and improvements in medicine. During the 20th century average American
lifespan extended at the rate of about three months a year, leading to today’s
average of just under 80. In 100 years
we experienced the same rate of increase in lifespan we previously experienced
over 3000 years.
What is still possible going forward? It will not be possible to extend our lives
beyond that of the oldest recorded human by continuing the same methods we used
previously (improved nutrition, reduction of disease, improved lifestyle,
improve safety). So what else can be
done to extend lifespan?
To answer this we first need to understand better what aging
is. Is aging a unified process, or a
collection of separate and independent aging processes? Is aging a degradation of the body, or an
increase of accumulated knowledge, or a reduction of stem cells? There is a lot of debate in the scientific
community around what aging really is.
Also, there’s chronological aging and biological aging – the two don’t
correlate the same way in all people.
There’s a big movement now to find the biological markers of
aging. There’s a lot of progress in
understanding the mechanisms of aging, but still no linking it to an overarching
system of aging.
Another question is whether there’s an evolutionary
imperative for us to die of old age? It
doesn’t look like it – evolutionary selection works on reaction to environment
or capabilities; there doesn’t seem to be an evolutionary system for cutting
life off arbitrarily after a certain amount of time. This used to correlate because with age
capabilities degraded, but if they don’t, there doesn’t seem to be an
evolutionary imperative to die.
Another thing to consider is that we are all decedents of
humans who are survivors of near mass-starvation events; in several times in
history the human population was reduced to a few thousand people (as recent as
75000 years ago). This means that our
ancestors were those who survived through incredible hardship, and we are
descendants of these super resilient people, and we carry that resilient DNA. If we can activate that we could possibly tap into some of that resiliency.
Alternatively, we can look at the longest living human. The most credible record of longest living human
is a French woman who lived to the age of 122.
There are also groups of people living to over 100 years old, and when
you examine them to see what they have in common, you see it’s genetics. Generally people who live very long lives
live well in their long lives.
Another area of study is comparative biology of related
animals. For example, a mouse can live
up to about 3 years in captivity, while its relative the naked mole rat can
live up to 31 years – without showing signs of aging. They also do not get cancer. Another species studied is clams – regular clams
live to about 15 years, but the ocean quahog clam can live several hundred
years, with the oldest measured at 507 years old (clams add a ring to their
shell every year, like trees). They can
live this long because of a low metabolism and mechanism to prevent
oxidation. A third example is the jellyfish,
who have a lifespan ranging from a few hours to several months (depending on the
species). However, there is one species
of jellyfish who is effectively immortal, because it can transform from adult
to a polyp, essentially reversing aging, over and over.
Experimentation has been held in roundworms that have been
selectively bred to long life. Genetic
analysis of roundworms of a long line of extended life compared with genetic
data of regular roundworms shows there are relatively small number of genetic
differences between the two types that can cause double or quadruple life (and
healthier lives). So scientists are
studying the tradeoffs of turning these genetic markers off or on.
Some strategies for increasing lifespan:
Short term strategies:
- Things we already know: exercise; low calorie, mostly plant-based diets; strong social networks; having a sense of purpose. Exercising 1.5 hours a week increases overall lifespan by 2.5 years over everyone else who doesn’t exercise. 2.5 hours a week, adds 3 years more; 1 hour a day gives 4 additional years.
- Calorie restriction diets: eating less calories than is required (~1200 calories a day). Research now shows you don’t need to constantly be on a calorie restricted diet permanently; 5 consecutive calorie restricted days, in two months of an entire year are enough to get the same effect.
- Drugs that trigger the effect of calorie restricted diets (Metformin, Rapamycin)
- Once identifying the genes that correlate with older life, you can replicate the enzimes these genes create in people who don’t have these genes, producing the same effects as if they had them
- Drugs that increase the number of times cells can reproduce
- Reverse aging process of cells (similarly to how the immortal Jellyfish work), but less drastically
- Blood rejuvenation – Research shows Parabiosis (sowing together a young moue and an old one, such that they share a blood system), rejuvenates the old mouse (while aging the young one). Similar rejuvenation happened simply by injecting human cord blood into an old mouse.
Medium term strategies:
- Large scale embryo selection through personalized precision genome sequencing
- Precision personal medicine
- Medical nanobots
Longer term strategies:
- Immortality. Increase the three months extension of life a year (current rate) to one year a year (unlikely).
- Downloadable brain that can be uploaded into a new body
We will need to redefine our definitions of humanity the
more we merge with technology.
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