Becoming Nicole is a book about two parents who adopt twin boys only to see, as they grew older, one boy begin to favor feminine things, then insist he was a girl. It promises to be quite compelling.
The statistics on such a phenomenon are rare so the numbers are difficult to use for any reasonable generality. Here are some numbers, as limited as they are.
Only about 5% of cross-dressers, or transvestites, have any desire to be the opposite sex, but those who do are often convinced they are a woman in a man’s body.
Fewer women believe they are men trapped in a woman’s body.
Perhaps one in thirty thousand of the population truly believe they are biologically different from their genetic makeup. At patients' request, 10,000 sex-change operations have been performed to date, (Israel & Tarver,1997), creating people physically of one sex but chromosomally of the other.
The percentage of homosexuality among co-twins is 11%.
Of four studied monozygotic (identical) male twin pairs, of which one was transsexual, the other twin was transsexual in only one case, so researchers concluded that genetic factors were most unlikely to be important.
The most unequivocal evidence is that brain microstructures are produced by long-continued behavior, rather than long-established brain structures causing the behavior. The brain changes physically in response to our behavior - London taxi drivers have an enlarged part of the brain dealing with navigation, violinists a larger area dealing with movement of the fingers of the left hand. There is no evidence that people are born with brain microstructures unalterable ever after - but there is strong experimental evidence that experience changes that microstructure. Transsexual brain differences would be more likely the result of transsexual behavior than its cause. (Presumably this might have "training" implications but who knows?)
Lady Gaga aside, there is no evidence for the political case that transsexuals were born that way.
The statistics on such a phenomenon are rare so the numbers are difficult to use for any reasonable generality. Here are some numbers, as limited as they are.
Only about 5% of cross-dressers, or transvestites, have any desire to be the opposite sex, but those who do are often convinced they are a woman in a man’s body.
Fewer women believe they are men trapped in a woman’s body.
Perhaps one in thirty thousand of the population truly believe they are biologically different from their genetic makeup. At patients' request, 10,000 sex-change operations have been performed to date, (Israel & Tarver,1997), creating people physically of one sex but chromosomally of the other.
The percentage of homosexuality among co-twins is 11%.
Of four studied monozygotic (identical) male twin pairs, of which one was transsexual, the other twin was transsexual in only one case, so researchers concluded that genetic factors were most unlikely to be important.
The most unequivocal evidence is that brain microstructures are produced by long-continued behavior, rather than long-established brain structures causing the behavior. The brain changes physically in response to our behavior - London taxi drivers have an enlarged part of the brain dealing with navigation, violinists a larger area dealing with movement of the fingers of the left hand. There is no evidence that people are born with brain microstructures unalterable ever after - but there is strong experimental evidence that experience changes that microstructure. Transsexual brain differences would be more likely the result of transsexual behavior than its cause. (Presumably this might have "training" implications but who knows?)
Lady Gaga aside, there is no evidence for the political case that transsexuals were born that way.
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