Genetics
— Ambroise Paré (1510 – 1590), Des
Monstres et Prodiges, quoted by Francois Jacob, The Logic of Life (1973).
In the family of Lepidus at Rome there were three, not
successively but by intervals, who were born with the same eye covered with a
cartilage. At Thebes there was a race that carried from their mother’s womb the
form of the head of a lance, and he who was not born so was looked upon as
illegitimate. And Aristotle says
that in a certain nation, where the women were in common, they assigned the
children to their fathers by their resemblance.
— Michel Eyquem de Montaigne (1533 – 1592).
Jacob Ruhe, surgeon in Berlin was born with six digits on
each hand and foot; he had this peculiarity from his mother Elisabeth, who had
it from her mother. Elisabeth transmitted it to four of her eight children she
bore to Jean-Christian Ruhe, who had nothing extraordinary about his feet or
hands. Jacob Ruhe, one of the six-digital children … had six children; two boys
were six-digital … From this genealogy, which I have followed with exactitude,
six-digitism is seen to be transmitted by both the father and the mother.
— Pierre Maupertuis (1698 – 1759), Letters.
Among all the numerous experiments made, not one has been
carried out to such an extent and in such a way as to make it possible to
determine the number of different forms under which the offspring of hybrids
appear, or to arrange these forms with certainty according to their separate
generations, or definitively to ascertain their statistical relations.
— Gregor Mendel (1822 – 1884), Experiments
in Plant Hybridisation.
Experience with artificial fertilisation, such as is
effected with ornamental plants in order to obtain new variations in colour,
has led to the experiments which will here be discussed. The striking
regularity with which the same hybrid forms always reappeared whenever
fertilisation took place between the same species [i.e., hybrid form] induced
further experiments to be undertaken, the object of which was to follow up the
developments of the hybrids in their progeny.
— Johann Gregor Mendel (1822 – 1884), Proceedings
of the Natural History Society of Brünn, 1866, Rook, Origins and Growth of Biology, 296.
A hen is only an egg’s way of making another egg.
— Samuel Butler (1835 – 1902), Life and
Habit VIII.
We are not the stuff that abides, but patterns that
perpetuate themselves.
— Norbert Wiener (1894 – 1964) The Human
Use of Human Beings, Avon Books, 1967).
This leads him to the famous hypothesis that the gene is a
linear one-dimensional crystal, but lacking a periodic repeat: an aperiodic
crystal.
— Max Perutz (1914 – ), reviewing the work of Erwin Schrödinger, Nature, 326: 555, 1987.
When the war
finally came to an end, I was at a loss as to what to do … I took stock of my
qualifications. A not-very-good degree, redeemed somewhat by my achievements at
the Admiralty. A knowledge of certain restricted parts of magnetism and
hydrodynamics, neither of them subjects for which I felt the least bit of
enthusiasm. No published papers at all … Only gradually did I realize that this
lack of qualification could be an advantage. By the time most scientists have
reached age thirty they are trapped by their own expertise. They have invested
so much effort in one particular field that it is often extremely difficult, at
that time in their careers, to make a radical change. I, on the other hand,
knew nothing, except for a basic training in somewhat old-fashioned physics and
mathematics and an ability to turn my hand to new things … Since I essentially
knew nothing, I had an almost completely free choice …
— Francis Crick, What Mad Pursuit,
1988, 15 – 16.
And now the announcement of Watson and Crick about DNA. This
is for me the real proof of the existence of God.
— Salvador Dali (1904 – 1989), quoted by J. F. C. Crick in Of Molecules and Men.
All of these people, should they desire, can indicate events
and details they remember differently. But there is one unfortunate exception.
In 1958, Rosalind Franklin died at the early age of thirty-seven. Since my
initial impressions of her, both scientific and personal (as recorded in the
early pages of this book), were often wrong, I want to say something here about
her achievements. The X-ray work she did at King’s is increasingly regarded as
superb. The sorting out of the A and B forms, by itself, would have made her
reputation; even better was her 1952 demonstration, using Patterson
superposition methods, that the phosphate groups must be on the outside of the
DNA molecule. Later, when she moved to Bernal’s lab, she took up work on
tobacco mosaic virus and quickly extended our qualitative ideas about helical
construction into a precise quantitative picture, definitely establishing the
essential helical parameters and
locating the ribonucleic chain halfway out from the central axis.
— James Watson, epilogue to The Double
Helix, Penguin Books, 1970, 175.
The common tortoiseshell cat, which has long been of
domestic interest because male tortoiseshells are so very rare, has recently
become of scientific interest also, as an example for a new theory of the
action of sex-chromosomes in mammals.
The genes concerned in the development of the tortoiseshell
colour lie on the X chromosomes …
The two sexes have equal numbers of autosomes, but females
with their two X chromosomes, have a double dose of X-linked genes. One would
therefore expect that they would have twice as much of the gene products of
X-linked genes as males have, and that this would cause difficulty in the
cooperation of X-linked and autosomal genes during development. In fact, males
and females are found to have equal amounts of the products of X-linked genes.
The theory recently put forward to explain this is that one of the two X
chromosomes of female mammals is genetically inactivated or ‘switched off’ at
an early stage of development and, although still present in all cells, remains
dormant and produces no gene products throughout the further life of the
animal. Thus, in effect, both males and females have only a single dose of
X-linked genes.
— Mary F. Lyon (1925 – 2014), ‘The X Chromosomes and Gene Action in Mammals’, Penguin Science Survey 1967, Biology,
121.
Indeed, the recipe analogy is really rather a good one,
while the blueprint analogy, although it is often unthinkingly used in
elementary textbooks, especially recent ones, is wrong in almost every
particular.
— Richard Dawkins (1941 – ), The Blind Watchmaker, Penguin Books, 1988, 296.
On the other hand, in one particular type of cell, those of
the fly’s salivary glands, it has lately been discovered that the chromosomes
are greatly extended. If the hereditary factors, strung out along the
chromosomes, are correspondingly elongated, it is just possible that it may be
practicable to observe them individually.
— A. W. Haslett, Unsolved Problems of
Science, London 1937.
It is a fact of some little importance to us, that
peculiarities appearing in the males of our domestic breeds are often
transmitted either exclusively, or in a much greater degree, to males alone.
— Charles Darwin, The Origin of Species,
1st edition, 1859, 13.
The Party, the Government and J V Stalin personally, have
taken an unflagging interest in the further development of the Michurin
teaching.
— Report to the Lenin Academy of Agricultural Sciences, Moscow, 31 July – 7
August, 1948.
[Edwin Hubble] told me a sad and odd thing, which is that
the party line has begun to get into Russian astronomy — that there is an
orthodox doctrine regarding the origin of the solar system and that those who
deviate from it are abused. They will soon, no doubt, suffer from the fate of
the bourgeois-idealist Mendelo-Morganists in the field of genetics.
— Aldous Huxley, letter to Matthew Huxley, 1949, Letters of Aldous Huxley, Chatto and Windus, 1969, 606.
But I am strongly inclined to suspect that the most frequent
cause of variability may be attributed to the male and female reproductive
elements having been effected prior to the act of conception.
— Charles Darwin, The Origin of Species,
1st edition, 1859, 8.
In the course of this work, animals and plants have been
drugged, poisoned, intoxicated, illuminated, kept in darkness, half smothered,
painted inside and out, whirled round and round, shaken violently, vaccinated,
mutilated, educated and treated with everything except affection from
generation to generation.
— H. J. Muller (1890 – 1967).
If the factors in heredity are carried in the chromosomes
and if the chromosomes are definite structures, we should anticipate that there
should be as many groups of
characters as there are kinds of chromosomes. In only one case has a sufficient
number of characters been studies to show whether there is any correspondence
between the number of hereditary groups of characters and the number of
chromosomes. In the fruit fly, Drosophila
ampelophila, we have found about a hundred and twenty-five characters that
are inherited in a perfectly definite way…
If the factors for these characters are carried by the
chromosomes, then we should expect that those factors that are carried by the
same chromosomes would be inherited together, provided the chromosomes are
definite structures in the cell.
In the chromosome group of Drosophila there are four pairs of chromosomes, three of nearly the
same size and one much smaller. Not only is there agreement between the number
of hereditary groups and the number of the chromosomes, but even the size
relations are the same, for there are three great groups of characters and
three pairs of large chromosomes, and one small group of characters and one
pair of small chromosomes …
— Thomas Hunt Morgan (1866 – 1945), A
Critique of the Theory of Evolution, 1916, reprinted in The Autobiography of Science, Moulton
and Schifferes, John Murray, 1963, 590.
[Here, Morgan has used the old name, Drosophila ampelophila, for the fruit fly Drosophila melanogaster.]
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