I saw on BBC News yesterday that Belgian top model Hanne Gaby Odiele revealed that she was intersex. Genetically she is a man (XY chromosome pair), but she was born with androgen insensitivity syndrome (AIS), meaning that her body is unresponsive to testosterone, which in turn prevents the masculinisation of male genitalia and the development of male secondary sexual characteristics at puberty.
Seeing her face, it struck me how her traits seemed considerably more masculine than a typical woman. There is a very boyish quality to her traits, which is completely understandable since she is really a grown-up boy that never underwent puberty. More than that, even women produce a small amount of testosterone, which can masculinise a bit their traits and behaviour and increase their sex drive. Here, Hanne Gaby appears to be completely immune to the effects of testosterone, so that her facial traits would have been less affected even that those of typical XX women.
We had discussed a few months ago whether Y-DNA influenced looks and behaviour. It had been suggested that testosterone alone was responsible for the masculinisation of traits. I replied that it was unlikely considering that boys and girls look very different already before puberty. A counter-argument is that the masculinisation process started in uterus. But in the case of androgen insensitivity syndrome it doesn't, since the foetus is genetically insensitive to testosterone and other androgenic hormones. Therefore, if a genetically XY person suffering from androgen insensitivity syndrome looks more masculine than an XX woman, it means that some gene(s) on the Y chromosome is responsible for this sexual differentiation, and that it is not just the result of testosterone. It makes sense since a female body builder taking large amounts of testosterone with never look like a man, just a muscular woman.
If one or several Y-DNA genes affect in some way facial traits, then it would be logical to think that mutations in that gene could also modify, even if only slightly, the masculine traits of the carrier.
Seeing her face, it struck me how her traits seemed considerably more masculine than a typical woman. There is a very boyish quality to her traits, which is completely understandable since she is really a grown-up boy that never underwent puberty. More than that, even women produce a small amount of testosterone, which can masculinise a bit their traits and behaviour and increase their sex drive. Here, Hanne Gaby appears to be completely immune to the effects of testosterone, so that her facial traits would have been less affected even that those of typical XX women.
We had discussed a few months ago whether Y-DNA influenced looks and behaviour. It had been suggested that testosterone alone was responsible for the masculinisation of traits. I replied that it was unlikely considering that boys and girls look very different already before puberty. A counter-argument is that the masculinisation process started in uterus. But in the case of androgen insensitivity syndrome it doesn't, since the foetus is genetically insensitive to testosterone and other androgenic hormones. Therefore, if a genetically XY person suffering from androgen insensitivity syndrome looks more masculine than an XX woman, it means that some gene(s) on the Y chromosome is responsible for this sexual differentiation, and that it is not just the result of testosterone. It makes sense since a female body builder taking large amounts of testosterone with never look like a man, just a muscular woman.
If one or several Y-DNA genes affect in some way facial traits, then it would be logical to think that mutations in that gene could also modify, even if only slightly, the masculine traits of the carrier.
