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>> Ladies and gentlemen welcome to the 2013 Royal Society GlaxoSmithKline Prize
Lecture. I'm Jean Thomas, I'm the Biological
Secretary and I have the housekeeping duties of asking you to turn off your
mobile phones, please, because the lecture is being recorded and webcast.
And also, to tell you in the that actually, I hope, unlikely event that
there's a fire, you don't go out through the usual doors but you, because of the
snow and whatever, you go out through these doors instead.
So, 2013 is the Royal Society Year of Science and Industry.
This is the year when the society will showcase excellence in UK industrial
science and strengthen links between the society industry and academia.
The Royal Society recognizes that world class research and development in the UK
industry is essential for transforming innovative ideas into commercially
successful products into its economic growth and securing the science space.
And it will be proactive in anticipating, understanding, and responding to the needs
of industry's scientists. Symposia and meetings with high industry
interests have been added already to the society's calender which already includes
longstanding initiatives in scientific excellence, such as the Royal Society
Industry Fellowship and the Brian Mercer Awards for Innovation and Feasibility.
So, the year of science, science and industry will bring a renewed focus on
engaging with the industrial sector to develop cogent arguments that high level
investment in the UK science space is essential for international
competitiveness. Something we would all, I'm sure, sign up
to. Now, to the prize and the lecturer, the
Royal Society GlaxoSmithKline Prize and Lecture is awarded biannually for original
contributions to medical and veterinary sciences published within 10 years of the
date of the award. The prize consists of a very nice gold
medal, an even nicer check for 2,500 pounds, and the recipient is called upon
to deliver an evening lecture at the Royal Society which is why we're all here this
evening. And this is really a, a capacity audience,
and the reason we're a few minutes late starting is that there is an overflow
room, and I don't remember that in the last, certainly, in the last four years of
chairing these evening lectures. So, Adrian has really put in a big crowd
tonight. So, no pressure there, Adrian, at all.
It was, the award was initially established following a donation from the
Wellcome Foundation. First award was made in 1980 the centenary
of the work and foundation and since 2002, it is being supported by GlaxoSmithKline
Limited. So, this year's recipient of the prize is
Adrian Bird an old friend and colleague, I'm delighted that he's received this
award. Adrian has held the Buchanan Chair of
Genetics at the University of Edinburgh since 1990.
And he's a member of the Wellcome Trust Center for Cell Biology in Edinburgh.
His research focuses on the basic biology and biomedical significance of DNA
methylation and other epigenetic processes.
His laboratory identified CpG islands as gene markers in the vertebrate genome.
And he discovered proteins that read the DNA methylation signal to influence
chromatin structure. Mutations in one of these proteins, MECP2,
and I'm sure we'll hear a lot more about this, this evening, causes the severe
neurological disorder Rett Syndrome, which is the commonest genetic cause of mental
retardation in females. Adrian was made a Fellow of the Royal
Society back in 1989. He's received several awards, numerous
awards for his work, including notably the Louis-Jeantet Prize for Medicine, the
Charles-Leopold Mayer Prize of the French Academy, and the Gatineau Prize.
This evening, it's the turn of GSK and the Royal Society to give him this special GS
Royal Society, GSK prize. And has to give his lecture in order to
earn that. His lecture is entitled, as you can see,
Genetics, Epigenetics, and Disease. So, Adrian, over to you.
>> Thank you very much, Jean. Thank you very much for this award.
It's a great honor to, to be asked to give this lecture.
And thank you very much for braving the elements to come and listen.
I think, probably the title of Genetics, Epigenetics, and Disease is broad enough
that it sounds like it's going to change all our lives in this next 45 minutes.
But in fact, I'm going to focus on a relatively small part of it ultimately.
But I'm going to start off reasonably broad.
There's one deliberate mistake on the, the first slide.
I hope it's the last one. It's the year.
So let's go back in time to the draft sequence of the human genome because this
was a, heralded as a, a time when biology really became a, a hard science.
If you like, it was seen as the, the beginning of the end.
We now knew the entire code for all, we knew the sequence of all the genes
required to make a human being. But it's pretty clear that it was actually
the end of the beginning. And the somewhat apocalyptic predictions
that now one simply had to automate, the discovery of all the medical innovations
that would result from the genome sequence was premature.
In fact, it's likely in my opinion that there's still another century of biology
to be done and this will be an exciting century of discovery converting the
promise of the genome into the reality of biomedical applications.
And that, one of the issues I think that, that, that we would really love to be able
to solve, a big, a big question if you like, is where DNA, despite being the
thread of life, you can put it in a tube and gaze, gaze at it for as long as you
want and it remains utterly dead. So the question is really what does it
take to make it alive? When Craig Venter synthesized a bacterial
genome an important synthetic biology milestone, it had to be put into a living
cell before it became alive. How can one bypass that?
As the chemists say, you only really understand something if you can make it.
We can't actually make life but it would be good to know some of the rules required
to do that. So, some key unanswered questions about
the genome that, that remain and this is only a selection.
First of all a basic fact, genes make proteins, here is the chromosome, here is
the sequence of the genes, there is the RNA.
It encodes the sequence of the amino acids that lead to the protein that folds up to
then do all the lifelike things that are required.
But how are only the right genes expressed in a cell type?
This has been a question, a long standing question.
Do we know the answer to it? Why globin is expressed in blood cells and
keratin is expressed in skin cells, etcetera.
We, we approximate knowledge about it, but actually, there's an enormous amount to
find out. Most of the genome is actually
inaccessible. This is this gray, it's rather difficult
to look at this picture I think because the DNA is gray and looks although it
should be in the background but this is a nucleusome, the repeating unit of the, of
the chromosome, if you like. The fundamental repeating unit.
And the DNA clings to the outside of it. And proteins that want to make genes
active, can't actually get at the DNA properly.
So, how does the gene activation machinery gain and how does it keep access?
Again, we have some beginning answers to this, but we don't, by any means, have a
full picture. Protein-coding DNA sequences are only 1%
of our genome. So, if you look at a piece of the human
genome, you see these vertical stripes correspond to the bits of this gene that
are separated from each other. In fact genes are fragmented and they are
a tiny minority of all the DNA. What is the rest of it for?
There is an enormous, there's a vast majority that is, that we can't explain.
This isn't the case with all organisms. This, for example, is yeast, and you can
see now the genes are packed together. It's difficult, it used to be said
casually that the rest of this DNA was just junk.
But now, it's sort of almost politically incorrect to call it junk.
It's particularly after the encode project which found lots of potential regulatory
sequences throughout here. So, this other DNA is doing stuff.
And perhaps, it's doing stuff that makes for example, humans and other mammals far
more complex than yeast. So finally, there are questions almost
sociological questions. Does the environment have any impact on
gene expression? And this is a, a question I'll allude to
in a moment. But it's not one that is the main subject
to this, this talk. So, I put in the title Epigenetics because
I'm quite mine, our work is quite often described as epigenetics.
It literally means above or in addition to genetics.
But the definition has been controversial and I'm just going to skim somewhat
lightheartedly over some of this because it's, it's at meetings to do with
Epigenetics. One can see various opinions expressed
with varying degree, this one I believe was in Barcelona with great vehemence.
So, let me just try to sort of consolidate this.
The original epigenetics definition comes from Conrad Waddington, who was actually
my predecessor as Buchanan Chair, Chair, Chair of Genetics in Edinburgh.
And what he meant was in contrast to pre-formationism, but the development
proceeded by the gradual unfolding of the information in the genes, to produce the
whole organism. So, for him, how information of the genes
is read during embryo, during embryonic development to give the whole organism was
the essence of what epigenetics was about. We would now call this developmental
biology. How the genotype gives rise to the
phenotype. But it's acquired, or a sort of, a special
status in epigenetics, really, because of this iconic picture, the epigenetic
landscape. I'm not going to dwell on this either.
Because quite honestly, having had it explained to me several times, I'm never
totally sure, exactly how this helps. It's a picture of a bull rolling down a
hill. The number of options for the bull get
progressively less. But I don't feel that this encapsulates
anything very useful. This, however, is a fundamentally
important question that remains on our agenda.
Second definition of epigenetics which is rather different has actually different
origins epistemological origins. How characteristics are inherited across
cells or organism generations without changes in the DNA, its sequence, itself.
An example of this is this cat, the so-called tortoise shell cat, or calico
cat, in, in, in the US, which has these patches of fur.
It has two x chromosomes. One of them has a gene that gives black
fur, the other one has a gene that gives orange fur, and cells early in
development, inactivate one or the other of those chromosomes for, for reasons we
don't, which I will, I will come back to actually, a little bit later.
And you get a patch of skin because the cell that originally inactivated the
orange fur gene gave rise when it divided to cells that did exactly the same thing.
So, that was inherited. All the gene or the, the DNA is still
there in these cells, in, in the orange ones, and the black ones, but there is
difference that is inherited and that's epigenetic according to this definition.
So, heritable traits of this kind might be influenced by the environment.
And this is sort of revitalized that an ancient argument about nature versus
nurture, where nature is genetics, the idea that we're, our genes are, are in