Quote from: Releca on October 11, 2014, 12:31:19 PM
http://www.quora.com/How-does-a-single-chromosome-make-all-the-difference-between-how-female-brains-and-male-brains-work
This link is a good article and shows the only real difference genetically. Every human on earth is female up until a certain point where a genetic change occurs making you born male. There is also a third gender where the Y chromosome is similar in size to the X and has a shorter arm going down. On the flip side the Y chromosome is shrinking and some believe it may be going away leaving an all female population. Not fully proven just a theory.
Back to the topic for the story are you making a book based on gender bending or gender transformation since sexual preference is the same for natural born or born different. We are whom we are and who we like stays the same. Some traits changes with hormone change but straight or gay is who you are and its something you know just like your gender is who you are and not if you choose it. We choose when but not if.
Thanks for sharing this link with me

I got really into this since I came to accept myself as trans and susequently coming out. Since back then I´m reading everything on this I can get in my hands. I like to figure out thoroughly what´s the reason for being trans and this leads you into biology (evolutionary development and genetics).
What you´re pointing at is fundamentally right but by now genetics tend to create two species of humans, women and men. The process of creation, starting with meiosis in the male body by producing sperm (the male delivers either the Y or the X chromosome in his single sperm which is inflitrating the egg hence creating an XX chromosome set or an XY chromosome set, thus letting the embryo develop in each "inprogrammed" way. So far the truth we all have been teached in our biology classes.
But it´s not that easy. As the Dwyer- and de-la-Chapelle-Syndrome shows, one can develop in each direction reversely regardless your primary chromosomal setup. Not to mention the XXY-syndrome or Klinefelter-syndrome which inflicts logically only phenotypical males. Furthermore, recent studies show that the chromosomal setup can show up to 4 (!) chromosal fixtures, like XXXY, XXYY, XYYY, XXY, XYY and so on. As long as there is one X chromosome the embryo will develop into a living human being. YY setups are inevitably dead.
Above all, these settings have no proven influence on brain development in the embryo, thus subconscious sex can differ from chromosomal sex, i.e. Transsexuality. And this is the most interesting but yet the most unexplored realm in evolutionary development. Scientists just don´t know exactly what makes the brain female. They consider hormonal fluctuations in the womb as a main reason for leaving a chromosomal male baby with a female brain.
For example, the forefinger-ring finger relation is an indicator of testosterone in the womb and the embryo itself. Experiments with mice showed that, the ring finger posesses receptors for testosteron, thus the ringfinger grows longer under the influence of testosterone in the womb. That´s why most women have a longer forefinger rather than a longer ring finger and in males it´s exactly reverse. If I look at my hands, on both sides the forefinger is way longer than the ring finger, showing that I have not been exposed to testosterone in the womb as I should have been for developing fully as male. And I´m transsexual. Accident or context? I believe this no accident, although I don´t know my chromosomal setup. Do you? Mine will be examined by my Endo by end of this year and I´m quite curious

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Personally, I believe that, in most transsexuals the SRY is not completely working, thus sending signals to mother´s body for holding back the testosterone flooding which overwhelms the male embryo in the womb and therefore the brain will never be exposed to an amount of testosterone necessary for developing into a male brain.
Back to your initial statement. Every Embryo starts out as female and if something (genetically or hormonal) is not in the correct ratio, the child will be either transsexual or in other cases intersex. But this has yet to be proven scientifically.
xoxo
Anna-Maria