Posted on 09/15/2009 11:00:27 PM PDT by neverdem
The first words ever spoken, so fable holds, were a palindrome and an introduction: “Madam, I’m Adam.”
A few years ago palindromes — phrases that read the same backward as forward — turned out to be an essential protective feature of Adam’s Y, the male-determining chromosome that all living men have inherited from a single individual who lived some 60,000 years ago. Each man carries a Y from his father and an X chromosome from his mother. Women have two X chromosomes, one from each parent.
The new twist in the story is the discovery that the palindrome system has a simple weakness, one that explains a wide range of sex anomalies from feminization to sex reversal similar to Turner’s syndrome, the condition of women who carry only one X chromosome.
The palindromes were discovered in 2003 when the Y chromosome’s sequence of bases, represented by the familiar letters G, C, T and A, was first worked out by David C. Page of the Whitehead Institute in Cambridge, Mass., and colleagues at the DNA sequencing center at Washington University School of Medicine in St. Louis.
They came as a total surprise but one that immediately explained a serious evolutionary puzzle, that of how the genes on the Y chromosome are protected from crippling mutations.
Unlike the other chromosomes, which can repair one another because they come in pairs, one from each parent, the Y has no evident backup system. Nature has prevented it from recombining with its partner, the X, except at its very tips, lest its male-determining gene should sneak into the X and cause genetic chaos.
Discovery of the palindromes explained how the Y chromosome has managed over evolutionary time to discard bad genes: it recombines with itself. Its essential genes are embedded in a series of eight...
(Excerpt) Read more at nytimes.com ...
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Like a certain hermaphrodite world leader?
So to cool neverd
Fascinating would be an understatement. The part about the mutual pair repair quality seems a bridge to far, let alone a special case lacking the feature… New vista.
Tanks for the pop. Rab
“Like a certain hermaphrodite world leader?”
Whom? Thanks in advance.
When the Y chromosome is damaged, you get a Democrat.
“Isodicentric Y Chromosomes and Sex Disorders as Byproducts of Homologous Recombination that Maintains Palindromes”
Well - there goes the mood I had when I first saw “sex anomalies” in the title!
Turner syndrome(XO), poly-x syndrome(XXX), Jacob syndrome(XYY) and Klinefelter syndrome (XXY)
And this explains Nancy Pelosi how?
ML/NJ
The ‘One’ is all sexes, all beliefs, and all personal redemptions.
Akhenaten.
Voting "present" from day one?
This is a cool discovery. Ain’t this stuff fascinating?
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Hey, if there aren't some anomalies, ya just ain't doin' it right. |
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