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time there's more to life in science and today will talk about the genetics of
autism because that's what's been going through the world press over the last
week
ever since on
april the fourth twenty twelve
the journal nature
published three papers
showing eugene supporters
these are not
the first jeans ever associated with forces and they certainly will be the
last
and they're not even
lodging effect size
nevertheless it's a very important set of papers because it represents
potentially turning point in on the stand and what isn't
and the genetic support
so what i want to be as i want to give you the full background to all of this
so you can see the costly advances in understanding that we have made
i would do this
video tim allen for past first class
uh... current understanding autism
second part
the history over understanding of autism
incredible advances in
uh... genetics and molecular genetics that we have made of the prospect of
case
and then forgot
i'll go straight into these
three pages
and that conclusion so you can see
uh... values
in the broader context
hotwire what is what is it
right these days we talk about quotas and spectrum disorder csd
classical system which is much more associated with mental retardation
out the frequency of that in the population
would be several cases per one thousand
but then there was also asked for syndrome
which we now believe to basically be and the milder version of the same thing
but because we believe in tennessee margins they're putting this
bracket
same bracket called espy
now what's the frequency of hasty in the population
but in two thousand six it was one hundred and ten
and just last month that's march twenty twelve
and new rate was published by the cdc
who've won in eighty eight
so there is fresh debate going on as to whether this increasing rates is because
are tightening since
inspection
or because that's not true
changed me until i read
uh... autism shows itself
before age three and it is believed to be associated with brain development
there's plenty of theories going along with
usually was
regard to connectivity
overgrowth developmental timing that kind of stuff
autism is also strongly
genetic
uh... but not exclusively genetics as they could also be biological factors
promote school course waters
vaccinations are not one of those
uh... ever since the scariest fled out this is being looked into the following
and there's a absolutely no sissy action between autism
and vaccination
and the original paper to make the claim
was actually fortunate
uh... or chisholm itself
or pay esteem both of them
uh... multi employer some girls about five times higher than boys and girls
the symptoms when you see in terms of autistic children
is that they are socially withdrawn
um... they don't make so much fun contact
for a are and that's the motion involves and they have a much higher preference
for
memorizing system icing
and then faxed this kind of stuff
can in fact
discriminative preference means that about
ten percent of them
how poor we called song to sing
uh... and this comes from the french diffusive home white school
basically because these kids show exceptional capabilities
and these kind of analytic
or memory related trips
now if you see in the nineteen eighty eight film rainman
ducts fictional buckets of show representation
upsetness
posterior brief history of autism
the word autistic
was first used by hans asked that their
in vienna
to describe the sole purpose of the group of children
that he was examining
of the work porches and was then used
five years later nineteen forty three
uh... in the states by kite by the name of the encounter
and once
or too sick children were described obviously there was uh... a lot of
interest in explaining why i want to some came about
now at that time in the nineteen fifties in the nineteen sixties
people believe that uh... you physically hearings was
whose genetic was inherited from your parents
your behavior was essentially a blank slate so the personality that you
developed
disorders included
uh... was essentially because of your treatment
so what
child psychologist it was went into the homes of autistic children and examine
the social dynamics
finding that the parents of autistic kids hope kulbir
with their children and most parents
they came up with this theory of the refrigerator muck
it didn't occur to them
that maybe if you have a child who is a copy unresponsive
too
uh... any emotional behavior
that often months and years
you just might be more practical
in your treatment of that
but anyway
this refrigerator among right here was was title for a long time causing loss
distressed parents
interest in the sixties
academics stossel to some academic started to is is this
now when we got into the nineteen seventies out and there was more
interesting genetics
all season was export from the genetic aren't looking at her own family pat
since the first
twin studies of waters happened in nineteen seventy seven
and then through the eighties in these studies
though they were small
started to show vast
forces and has strongly
genetic
basis
how much you know something's got a strong genetic basis
and obviously the next stage is going to find the jeans
puffery
okay how naive
back it's late and i'm glad i chose to do this impasse
brought his village in essex that you need to men
in fifty three the and structure of d_n_a_ was discovered
by francis creek and james watson
announced that the whole balk interests
three key developments uh...
that came from out in terms of technology now
firstly
in nineteen seventy seven french sang and developed a method of sequencing
d_n_a_ out
i need reading it
uh... and that was so important that he won the nobel prize for at least three
years later in nineteen eighty
in fact that was his second over price is one of only four people in history to
won the nobel prize twice
the others america red-blooded for physics and the chemistry
outline is growing who want to pick a mystery and fifties
and run by the new one for physics twice
joined bloody nhanh
invented the transistor
which is the fundamental component of whatever electronic device watching some
of the moment
second he development
was the pcl
and uh... nineteen eighty-three like cary mullis
and the p_c_r_ is basically a technology to
amplified d_n_a_ to photocopy adopt said that you can bet to study it so even
with tiny amounts
you can
uses
next year
um... in nineteen eighty four
alec jeffreys now settling jeffries
developed a d_n_a_ fingerprinting
so this is different from sequencing this is
finding
various places in your d_n_a_ which highly variable between people
so you take one b
you find out what to bring you up another place which venue another place
which credit you off
and with a sense of these
you actually have a profile
uh... for which you are unique
and that is
d_n_a_ fingerprinting and you can see how the pc on d_n_a_ fingerprinting come
together
to be such a powerful tool
in among forensic science
say let's put those aside a senate and now let's talk about
how teams impact on the seasons
malcolm originating status rework his
genetic defects
influence diseases
this chromosomal abnormality is wiped down syndrome
single gene disorders
one gene going wrong
do you see the disorder
an example saw cystic fibrosis and sickle cell disease
consultants of these being documented because that fairly straightforward
trellis
you just take a mock-up
or set of markers on d_n_a_
and you wash
how the disease goes down for families and you watch democracy and match
tomorrow
secretly find out which chromosome they are and then our own dollar macros and
pressure from the disease
thousands of these induction
now wants the third
uh... which is relevant or tourism schizophrenia a_d_d_
even disorders like anxiety and depression
multi gene disorders
these disorders usually have the genetic component an environmental com
and the genetic component genes can be added to the contract with each other
and they certainly contract with the environment
which makes a very very difficult to get a handle
now i went to the international society psychiatrist genetics conferences for
about two thousand two thousand five
so i'm still
firsthand the uh... frustrations and difficulties of
researches
who were not finding
genes in these polly
disorders
or they will find in jeans but then other people weren't replicating what
they were finding
and so
there was a need for clean the designs and and bigger sample sizes and it's
always been a sample sites to finding someone jeans
but one interesting technology you should know about that
when you're comparing
someone who's affected
control group
they might not have simply genetic backgrounds and i can really mess up
your studies
today security technology
that has been in useful over ten years now
and that is using trios c taken effect it individual
and you take that d_n_a_
and did you take the d_n_a_ also
with their parents and mother and my father
now throw any change of we have
often
x my grandsons we have two copies
one from your mother and one from your father
dot wilson means
there is a copy from your mother things we didn't get and copy thank you
from your father that you didn't get so that this is really nice
tidy designed to be neighbors compat two copies that you've got
associate with your disease
and the two copies
that you didn't get
okays a vast rears
one final thing that you need to know about human genetics jim all this time
before we move on to the actual papers
is the human genome project
and this is a
massive story
that i'll summarize it
very quickly for you
in nineteen ninety it was decided to have a world effort
on sequencing the human genome like with sunday's method just renewal
who all reading
one person's
from start to finish
billions of based test
it was planted this would take fifteen years in fact it finishing two thousand
and three uh... said it was two years early and that was partly because
there is a massive race on between the public effort and a private
led by a guy called crepe vendor
and cravens was also
threatening claiming
that he was going to go in patent
or the jeans that he was fine
and this course great outrage monks loss of scientists
and in march two thousand it took
president bill clinton
to step in and say human genes cannot be patented
you cannot go and burn them
whizzes
homestead big
guaranteed that term
the human genetics is free for us to be studying
hidup sabia
them to stop at the time
thoughts are
the long-term benefits and absolutely clear
the huge human genome project found
the essentially
um... there are twenty to twenty-five thousand jeans
um... and they occupy about one to two percent of the space of one of our
jeanne and was the rest is
job fossil records things like that
and also they accelerated to the all these efforts on the critics underrated
technologies
so that
if you look at the situation today just a few years back steve jobs
decided to have his own team and sequence
and also
the d_n_a_ off his chin the scripts
that cost him hundred thousand dollars
now at the moment the cost of having yo hope genome sequence is about one
thousand dollars in just a few years so incredible technological advance on that
front
and this has provided you now looking autism looking
genetics
with the information you need to understandings papers which were not
took proper the three papers
okay now don't worry about this because we've got or the information behind us
we can make swift work these papers
first of all bailout precedes that waters inspection disorders
throw classic
hard-core quarters 'em
remember that i was telling me about the method of trios
thousand for you
remembers telling me about the importance fill up sample sizes
welcome buying these three papers used
said nearly six hundred trio said six hundred individuals
and mothers and fathers
and in addition to that another almost one thousand people with hasty
and remember i was telling you about our sequencing
welding technology has come so far but movies people helping sequence and this
is the main
thrust of the paper
and uh... look and it's not just all of the urging them to do being sequence but
the expense
now remember listening interest before about that wanted to send eugene and
which actually does something that has a lot of teens which prudent and putting
out the proteins
of the building blocks of your body
well that's the extent that part of the g_m_ and that's doing the coding that
approximately one point five percent
so that these themes is being sequencing
there's exon's and comparing
those incase control designs
and that's the essence of what they're doing
to get the extra information and the extra power
to see what's going on
now one of the most exciting
aspects from these three papers
is the discovery of the importance of
denovo mutations so mutations
in jeans of interest associates with autism
but not another an option the father there just in the offspring
now if you would use the classic
gene hunting technology
all of um...
comparing convents visit this common values associated with this common man
disassociated
you wouldn't see that
kids from you when you actually do the sequencing the reading at the gym every
individuals script
for that g
did you get to pick up on this kind of stuff
using this method we've
nominated three more teams now associate resources and that will be many more to
come
but those will be coming to pass these people and their collaborators
acting more individuals with its the into the database and start sequencing
that too
until we get to the stage
wet
we have a set of genes
and we know that
any
modification of those jeans
runs the risk all feeding to autism or at least making a probabilistic
contribution
to the developmental
so you can see why
this new technology this colossal which is just being undertaken which certainly
possible
with the technology that we have today and with lots on four sizes
is actually the breaking
injecting point in terms of putting in the flood of genes which then hopefully
we can put together a look at their instructions
and see
why this important for brain development and how
normal development this autistic development
happens
uh... in the brain
very exciting time and it's kuwaitis great to see an
information coming from falling into science
it's not cutting edges
posse clouding edge
in which finding stop to crystallize
and then
eventually become the the pretty pictures and diagrams undergraduate
textbooks and who believe also in this case