The six biological karyotype sexes that do not result in death to the fetus are:
- X – Roughly 1 in 2,000 to 1 in 5,000 people (Turner’s )
- XX – Most common form of female
- XXY – Roughly 1 in 500 to 1 in 1,000 people (Klinefelter)
- XY – Most common form of male
- XYY – Roughly 1 out of 1,000 people
- XXXY – Roughly 1 in 18,000 to 1 in 50,000 births
When you consider that there are 7,000,000,000 alive on the planet, there are almost assuredly tens of millions of people who are not male or female. Many times, these people are unaware of their true sex. It’s interesting to note that everyone assumes that they, personally, are XY or XX. One study in Great Britain showed that 97 out of 100 people who were XYY had no idea. They thought they were a traditional male and had few signs otherwise.
Even today, we irrationally, and rather stupidly, think of someone as a “man” if they look masculine and as a “woman” if the look feminine. It’s entirely arbitrary and can lead to some significant misunderstandings of how the world
actually works.