Thoughts on Sex, Gender and Evolution.

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Thoughts on Sex, Gender and Evolution.

• Marianne J. Legato, M.D.
• With A Lot of Help from
• Charles Darwin et al.

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So weve Cracked the Genetic Code and
Defined The Human Genome So?
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Whats a chromosome? Whats a gene? How does it
work? Whats a mutation?
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Who exactly was Charles Darwin? What did he
say? (And why should we care?)
1809-1882
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What makes us male or female?
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XX
X
Y
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Do we need two sexes? (The Y chromosome only
arrived on the scene about 300,000,000 years
ago.)
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Does Sex Impact Gene Expression?
Thousands of genes show sexual dimorphism in
liver, adipose, muscle and the brain
they exhibit highly tissue-specific patterns of
expression.. We saw striking and measurable
differences in more than half of the genes
expression pattern between males and females. We
didnt expect that. no one has previously
demonstrated this genetic gender gap at such high
levels.
Thomas Drake, C0 investigator
Yang et al. Genome. 2006
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Does every cell in our body have a sex? Or are
some parts of us androgynous? Does every gene
work the same way in men and women? So do we
have (and why do we need) sex-specific tissues
and organs? (I think we do, and if you believe
Darwin, it equips us perfectly for the
environment. )
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What are genomic scientists doing worrying
about saying
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What Scientists are Doing

• Taking genes out and inserting others
• Making biologic specimens capable of reproduction
• Giving us a precise picture of who we are and the
  possibility of changing it.

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Evolution is no longer natural selection. With
the advent of genetic engineering, we can- and
are- changing very nature of created life.
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Imagine
Human cloning Engineering the characteristics of
new (human?) beings prepared for
specific functions (like war, for
example) Prolonging the life span
indefinitely Creating new biological systems
capable of reproduction (and if this is so,
also probably capable themselves of evolution)
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Genomic Science and Sex

• Will it be an advantage to retain two
• sexes?
• If we eliminate biological sex in new forms of
  life before we understand the nature and extent
  of its expression on genes, what will be the
  consequences to form and function?
• Does the study of the impact of sex on gene
  expression deserve more attention?

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What are scientists worrying about?
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Consider the Impact OfGenomic Science On

• The environment
• Economics
• The nature and number of living beings
• The redistribution of power (planned and
  unplanned)

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"Ever since the discovery of nuclear fission, the
possibility of powerful explosives based on it
had been very much in my mind, as it had in that
of many other physicists. We had some
understanding of what this might do for us in the
war, and how much it might change the course of
history.
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I chide Goldblatt for the incredible naiveté
he and the Defense Sciences Office displayed in
not thinking its plans to enhance humans would
arouse controversy. didnt it occur to anybody
that you were playing with fire?
Joel Garreau (in Radical Evolution)
Michael Goldblatt, former head of the Defense
Science Office
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What Scientists are Saying

• We are changing the rate and mechanisms of the
  evolution of living things profoundly.
• If there is a choice between preserving the earth
  in a viable state or continuing the human race,
  we will probably opt to continue the race.

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My guess is that if the question of human
extinction is ever posed clearly, people will say
that its all very well to say weve been a part
of nature up to now, but that at this turning
point in the human races history, it is surely
essential that we do something about it that we
fix the genome to get of rid of the disease
thats causing the instability, if necessary, we
clone people known to be free from the risk,
because thats the only way in which we can keep
the human race alive. A still, small voice may
at that stage ask, but right does the human race
have to claim precedence for itself. To which my
guess is the full-throated answer would be,
sorry, the human race has taken a decision, and
that decision is to survive. And, if you like,
the hell with the rest of the ecosystem.
Sir John Maddox, Former editor of Nature
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Prometheus, who gave men fire.