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									     EARLY HISTORY OF

EPIGENETICS
         From Jean-Baptiste Lamarck
            to Conrad Hal Waddington




                       Boris Vyskot
        Department of Plant Developmental Genetics
Institute of Biophysics, Czech Academy of Sciences, Brno
  Realistic Drama from the History of
Developmental and Evolutionary Biology
                  -
           in three acts
    (plus prologue and epilogue)
                  -
       taking place in Europe
from the beginning of the 19th century
    to the mid of the 20th century
Prologue: Theory of Adaptive Evolution (Lamarck)

Act One: Of Toads and Man (Kammerer)

Act Two: Creative Soviet Darwinism (Lysenko)

Act Three: Great Renaissance Heretic (Waddington)

Epilogue: Epigenetics (to be continued)
         Prologue


      Historic overture
or theory of adaptive evolution
Jean-Baptiste Lamarck (1744-1829)
• Theory of biological evolution
 Evolution (development) occurs from mineral forms to living
organisms, from simple forms to complicated ones, which result in
perfectly adopted organisms.

• Use and disuse of organs
 Organisms react on changing environment by development of
new organs or by changing the structure and function of current
organs.

• Inheritance of acquired traits
 Traits acquired during the life of organism are transmitted into
sexual progeny (discredited by Weismann).

Lamarck coined the term biology and invertebrates, and
invented the first evolutionary „soft“ theory. His theories of
adaption form a philosophical basis of modern epigenetics
Lamarck had a different opinion on evolution compared with
Darwin. He believed that simple forms of life continuously
pass to more complicated ones to become perfect, and are
transformed into new species.
Lamarck’s reputation suffered when
problematic experiments were made by
other researchers who wanted to
disclaim or support his ingenious ideas
       Act One



     How One Toad

Destroyed One Man’s Career
                       Starring

          baddie: Dr. Paul Kammerer
   (Vivarium Vienna, researcher, pianist, and lover)
 advocates: Prof. Hans Przibram (Vivarium, director)
          Prof. E.W. MacBride (zoologist)
prosecutors: G.K. Noble (keeper of reptiles, Alytes)
              H.M. Fox (zoologist, Ciona)
           J.R. Whitaker (marine biologist, Ciona)
   critics: Prof. R. Goldschmidt (geneticist, Proteus)
           Prof. William Bateson (geneticist)
epilogue: Lunacarskij: Salamandra, Russian film (1927)
A. Koestler: The Case of the Midwife Toad, book (1971)
The plot occurs in Vienna and runs
on pages of the famous journal Nature
at the beginning of the 20th century
Paul Kammerer (1880-1926) and environmental vitalism
Sequence ONE (Kammerer 1909)


SALAMANDRA
reproductive adaptation of two species of salamander

Salamandra maculosa (mottled, lowland)
Salamandra atra (black, alpine)

Change of environmental conditions (temperature,
humidity) leads to a modification of their reproductive
behaviour, the inheritance was not checked.
Sequence TWO (Kammerer 1912)


NEWT
environmental (experimental) manipulation of ontogenesis

Proteus anguinus, the blind cave newt

Exposure to red light does not cause pigmentation
of the skin and, thus, permits development of
completely functional eyes.
Inheritance of this developmental change
was not followed.
Sequence THREE (Kammerer 1923)


CIONA
experimental induction of a new trait and its inheritance

Ciona intestinalis, sea squirt (ascidian, Urochordata)

Amputation of siphon ends (stoma and anus) leads to
regeneration of prolonged siphons and this trait is inherited
by successive generations even without any other
amputation (“hyper-regeneration“).

Fox (1923) and Whitaker (1975) did not confirm
these results.
Sequence FOUR (Kammerer 1923)


TOAD
environmental induction of a new trait and its inheritance

Alytes obstetricans, midwife toad

Incubation of toads in water environment invokes
formation of „nuptial pads“ on forelimbs of males,
this trait is transmitted by sexual progeny even
without the inducing environment.

Noble (1926) documented injection of Indiand ink
in the Kammerer’s specimen.
                      Summary

Kammerer, P.: Breeding experiments on the inheritance
     of acquired characters. Nature 113: 637, 1923
Fox, H.M.: Dr. Kammerer’s Ciona experiments.
     Nature 112: 653, 1923
Kammerer, P.: The Inheritance of Acquired Characters.
     Boni & Liverlight, USA 1924
Noble, G.K.: Kammerer‘s Alytes.
     Nature 118: 209, 1926

… KAMMERER COMMITED SUICIDE .... 1926

Przibram, H.: Nature, 1926 (obituary)
Koestler, A.: The Case of the Midwife Toad.
      London 1971
Whitaker, J.R.: The case of the suspicious siphons Ciona
      revisited. Science News 107: 348, 1975
        Act Two



     The Drama Continues
             or
„the Creative Soviet Darwinism“
Plot occurs in the Soviet Union
and other communist countries
at the 30’s to 50’s of the 2Oth
century
Trofim Denisovic Lysenko (1898-1976)
         Lysenko, Trofim Denisovic
 Russian agronomist, father of „transmutations“

- as the President of The Lenin Academy of Agricultural
Sciences he has become the scientific and administrative
leader of Soviet biology in 40th to 50th of the XX century

- using a traditional process of vernalization (moistening
and cooling of seeds) he reputedly changed properties of
the spring wheat to the winter wheat)

- a part of the communist ideology exagerrating the influence
of environment on living organisms, rejecting genetics

- based on the work of the old orchardist Mitschurin,
in plant and animal breeding he continued such ideas
as vegetative hybridization
 Principles of „the Creative Soviet Darwinism“

- the basis of co-ordination of organisms and environment is
metabolism (exchange of substances)
- disturbance of metabolism results in loss of ability of selection
and creation of changes (mutations?)
- inheritance is the result of concentration of various
environmental factors assimilated by organisms in many
preceding generations
- evolution cannot proceed without inheritance of changes,
which have been acquired by the organism during its life
- inheritance in plants and animals can be controlled (only) by
environmental factors
    Nikolai I. Vavilov (St. Peterburgh: 1887-1943)
Geneticist and breeder, the father of Russian genetics
Prisoner Nikolai I. Vavilov (Saratov, 1943)
        Act Three


 Life and Ideas of the Great
    Renaissance Heretic

Conrad Hal Waddington
           Genetic assimilation in vitro
                   Conrad Hal Waddington (1953)




Phenocopy of mutation bithorax    Selection experiments on the„bithorax“
  (the second pair of wings)     reaction after aplication of ether on embryos
Other important roles of environment
unfolding of hidden genetic variation




    standard    “without cross-veins“


generation                                P    F1   F14

% „without cross-veins“ (heat shock)      23   79   97

% „without cross-veins“ (no heat shock)    0   0    1-2

    - the trait, once environmentally switched on,
         becomes assimilated in the genome
  Interpretation of genetic assimilation
canalization (co-ordination) = suppression of phenotypic variation,
assuring of “normal development”, roles of heat-shock proteins as
a buffer of “developmental protein factors”, restricted motion in
epigenetic landscape




critical points differently
sensitive to
environmental changes




                      wild-type   alternative phenotypes
            Epilogue

Inheritance is more complicated than
we (Mendel, Watson, Crick …) thought.

   Recent progress in epigenetics
   favours the ghost of Lamarck.

       Renaissance of heresy?

								
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