The 6 Most Common Biological Sexes in Humans

Many of you have expressed an interest in more of my personal essays; the documents I use myself to study various topics and take advantage of the so-called “orangutan theory”, which states that forcing yourself to write down your ideas, or speaking them out loud, even if your only audience is a large primate in a circus tent, shifts your brain into a logical mode that gives you a better understanding of what you believe, both inherently and explicitly.  I decided to share another one of the in-progress essays, though I modified it to read better online as if it were addressed to the blog audience by changing a small amount of the verbiage.  Again, just like my previous essay on religious beliefs manifesting through time, culture, and geographic distance, this is a work in progress that will change substantially by the time I stamp “concluded’ on it and feel as if I really have a handle on the subject matter.  It was not originally intended for public consumption as its sole purpose is for me to understand how the various components are connected.

There was a news story about a 66 year old man who discovered, during a trip to the doctor, that he was really a woman.  If you don’t have a biology or genetics education background, or never really took an interest in reproductive strategies of various animals and plants in nature, that might seem absurd, or even impossible.  Of course, it’s not.  It’s far more common than the general population realizes.

The Journal of the Royal Society of Medicine points out that one of the first modern cases came from the 1936 Olympics, hosted by Adolf Hitler.  An American named Stella Walsh, commonly called “Stella the Fella”, crushed the competition.  She always changed by herself and had muscle tissue and facial features that resembled a man.  The Olympic committee did an examination during which the members found that Stella was, in fact, both male and female.  Sort of.  She had ambiguous genitalia and it was impossible to determine her biological sex.  This remained a secret until Stella’s death in 1980 when “she was shot and killed in the cross-fire of an armed bank robbery in Los Angeles”.

Today, we have genetics and DNA that allows us to examine karyotype.  We know, without question, that humans are not just born male and female.  There are at least six biological sexes that can result in fairly normal lifespans.  (There are actually many more than six but they result in spontaneous abortion as the body knows the fetus won’t be viable so it is flushed out of the system in a natural process meant to minimize the amount of nutrients and metabolism devoted to growing non-viable offspring.)

The Six Most Common Karyotypes

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.

It Is Possible for Your Brain, Your Body, and Your Reproductive Systems to All Have Different Biological Sexes

What makes it even more complicated is that you cannot rely on karyotype alone to determine biological sex.  A few years ago, there was a story about a teenage boy who was, in all regards, perfectly normal.  He looked male, he acted male, he had a fully functional male reproductive system.  He suddenly became extremely sick.  He was growing sicker and could have died when it was discovered that he also had a female reproductive system internally.  When he menstruated once a month, the excess blood had nowhere to go since there was no available external exit, causing it to be reabsorbed into his body.  This boy was male.  However, he was also female.  It is a gross simplification to act as if he were just a boy.  He was more.

Even rarer are the cases of chimeras such as Lydia Fairchild, who have multiple sets of DNA in their body so that they are not the biological parents of their own children, even when conceived through regular reproduction and birthed entirely naturally.

The Case of Riley Grant

And then we get into the really interesting territory.  It is possible that your body, your brain, and your reproductive system could all be different biological sexes, or in some cases, biologically one sex but physiologically wired as another sex.  It seems crazy but it happens regularly on an ordinary statistical distribution so it is simply part of human reproduction.

Think about that for a moment.

An example is the case of Riley Grant, who has been documented in the news.  Riley’s body is biologically male.  She has, I believe, a standard XY chromosome.  She has a fully functioning male reproductive system.  However, Riley’s brain didn’t develop as male during gestation and was mapped as female.  We know from advances in neuroscience the past few decades that the differences between male and female brains are not insignificant – it influences everything from color perception to taste, scent, emotional reaction, empathy levels, rationality levels, pain tolerance, vocal inflection, and a host of many other factors.  This is easy to see on an MRI – male and female brains respond differently to different stimuli.  The largest study documenting the extent of the differences between male and female brains was done by Dr. Daniel Amen, who analyzed 26,000 people and found that the male brain has heightened activity in regions “associated with visual perception, tracking objects through space, and form recognition” and are 8% to 10% larger in mass size, while the female brain shows more overall activity, as well as increased blood flow in 112 out of 128 brain regions.

Riley’s parents realized this when they discovered her at 2 years old in the shower holding clippers against her penis saying, “It doesn’t go there.”  She kept insisting she was a girl.  Sure enough, a lot of medical tests later, that turned out to be the case.  That means that, in this case, the physiological sex mapping of the brain is different from the biological sex of the body.  Riley’s brain is wired as female despite having XY chromosomes.  There is no question about it.  It’s a fundamental, scientific, indisputable fact.  It is not a mental disorder.  She is not confused.  Her brain is of the same structure as the typical woman.  A century ago, she would have been written off as crazy or disturbed but our understanding of the interesting outcomes of biology now let us know that it’s a very real condition based upon demonstrable facts.

Sometimes, but not always, this condition is caused because a male fetus is immune to testosterone.  When this happens, the testosterone released by the mother’s body during development doesn’t trigger the signal to map the brain as male, and a female mind is created, despite the fact the genetic instructions from the chromosomes is busy making the physical body male.  The only way to remove the cognitive dissonance and prevent suicide, substance abuse, and a host of other coping mechanisms that lead inevitably to death and misery is sexual reassignment surgery, forcing the exterior body to line up with the brain.  This, in effect, removes the constant exposures to said cognitive dissonance, and leads to far greater physical and mental health.

(This is not to say everyone who wants sexual reassignment surgery is legitimately a case of a brain and body mismatch.  Some are simply mentally unhealthy and fixate on the notion of being transgender as a coping mechanism, only to regret the change later.  A sociological manifestation of this phenomenon is the so-called “pretendbians” – men who insist they are women, dress in women’s clothes, and present as women, but then wish to retain their male biological parts whilst saying that they are lesbians who want to date other lesbians.  This includes having penis-in-vagina sexual relationships.  These lesbians, who by very definition are not interested in having penetrative sex with a biologically male body, are then accused of being “transphobic” and creating – this is the actual term – a “cotton ceiling”; a play on words that borrows from the glass ceiling in female employment and the cotton construction of a typical pair of underwear.  It’s a disturbingly misogynistic thing to believe as it implies that the the biological female lesbians owe their physical and emotional affection to someone who demands it and is incapable of meeting their needs.  One author refers to these “pretendbians” as men engaged in a self-deluded form of “heterosexual kink”.  In any event, they do tremendous damage to the political efforts of actual transgender people, like the Riley Grants of the world, who should be protected from employment discrimination, given access to mental health resources during transition, and supported in school during early childhood when beginning hormone treatment to rectify what is a very real biological condition.  Men and women who fall into this faux form of transgenderism often display a litany of mental health and / or mood disorders.)

The Case of David Reimer

The flip case of Riley Grant is the now well-documented and studied case of David Reimer.  He was born a boy in 1965, one of two identical twins.  He was absolutely normal, XY karyotype, fully functioning reproduction system.  His parents wanted him circumcised but the doctor botched the operation so badly that they decided to castrate him and transform his body into a woman’s through the use of estrogen injections when the parents realized he would never have a penis or be able to enjoy sexual relationships with women.  The thinking at the time was the now-debunked idiocy that is known as the “blank slate” theory; that humans are entirely a product of their environment and we can adapt to anything.  The truth is, a lot of our personality is hardwired on a genetic level.

Despite putting David in “frilly dresses”, forcing him to play with female toys, calling him “Brenda”, and keeping the secret so that no one knew he was born a boy, David’s brain knew better.  He kept insisting he was not a girl.  He kept insisting he was not attracted to men, despite being told that, as a woman, he should be.  By 13, he had grown suicidal as the cognitive dissonance between what people were telling him and he saw when he looked in a mirror and what his brain knew inherently grew too great.  At 14 years old, he decided to live as a man, began taking testosterone injections, and undergoing cosmetic surgery.  He married a woman and became stepfather to her kids.  Only later did his parents confess what had happened to him, after he had finally decided he was willing to live as a man even if they didn’t accept it.

Nothing the doctors could do changed the fact that David was a male nor could they change his sexual orientation despite everyone around him insisting that he was a girl and was meant to date boys.  His brain knew better.  He was wired in a very specific way in the womb and no amount of elective cosmetic surgery or hormone treatment could change that.

Biological Sex Is Not the Same As Gender

What causes some confusion in the general public is the use of biological sex and gender as interchangeable terms.  They do not refer to the same thing.

• Biological Sex – Usually determined by karyotype.  The brain, body, and reproductive system can be different sexes, in the case of legitimate transgender people, where the brain physiology resembles that of the opposite sex, or biological chimeras.
• Gender – Mostly used for cultural behaviors such as dress, mannerisms, signs of deference, et cetera, that differentiate the sexes, gender itself is not entirely a social construct.  As already mentioned, neuroscience research over the past few decades indicates through an overwhelming amount of evidence that gender is not a “blank slate” that is imparted entirely by civilization, but rather has some inherent characteristics that manifest regardless of upbringing or environment.

This is why some fringe activists can seriously say, “You can be a woman with a penis”, while most of the world will look at them like they have lost their mind.  They are inherently using the term “woman” to refer to gender and not biological sex.  This difference in vocabulary is responsible for virtually all conflicts between groups on issues in this arena.  They do not realize they are using a phrase to refer to two separate things that are often, but not always, congruent.

The reality is the English language is woefully inadequate to address these biological, and in some cases, psychological, conditions.  Unlike many ancient societies, we lack the requisite terms to make a differentiation.  A person who is born male with a female brain and has sexual reassignment surgery can insist that she is a woman – and mentally, she is – but it is different than a fully formed, biological woman.  And therein lies the trouble.  Native American Indian tribes, Middle Eastern kingdoms … they had words to explain these things as they recognized reality a bit faster than we in the West have.  It’s probably time to recognize that more than 99% of us are male or female, but in a world with so many billions of people, that 1% is a heck of a lot of folks who are something else.  Trying to shove them into a binary system when the universe itself is not binary in this matter is a form of the mental model known as “greedy reductionism”.  It stigmatizes them for a physical trait that is entirely benign and it damages us by causing us to ignore reality; something that should be anathema to the rational thinker.

Follow Up Questions for Further Study

Here are some questions that I still need to address and consider:

• In the case of legitimate transgender individuals with a brain and body that are not congruent, the best mental health outcome is to begin the correction and transition process to lower cognitive dissonance as early as possible, before the onset of puberty.  However, if a mistake is made, the damage can be irreversible   How should society, particularly medical doctors, proceed with this knowledge?
• John Hopkins, one of the most respected medical institutions in the world, closed its gender reassignment center back in the 1980’s because the then-chairman of the psychiatric department, Paul McHugh, decided that he was helping mentally disturbed people mutilate their bodies instead of treating them to recognize reality.  However, as stated previously, the vast advances in neuroscience now tell us that gender is almost entirely “innate and immutable” from the time we leave the womb.  If you were in charge of John Hopkins, would you consider changing the institutions stance in light of the past twenty fives years of advances in understanding?  Why or why not?
• Does it change your opinion when you realize that even Iran, one of the most irrational and illogical societies on the planet, which often ignores scientific data, recognizes the condition and provides sexual reassignment surgery to individuals who are affected by the condition?  Yes, they do it under the idiotic guise of thinking that gay men want to become women, which has nothing to do with transgenderism as a vast, vast majority of gay men are so-called cisgendered (their biological sex lines up with their gender identity) but the practical outcome is, someone could transition, even if for the wrong reasons.
• Were you to have a transgender child, what would your course of action be?
• What would you feel, emotionally, if you discovered you were not an XY or XX male or female?  For example, if you were a male who was XYY?  Would it matter to you?
• Given that we now know humans are not made male and female, shouldn’t we come up with terms to describe the four other karyotypes that commonly manifest in births?  If so, what should we call them?
• Research the interesting phenomenon that discrimination against those who are not traditionally male or female are often treated with respect if, and only if, they “pass” and are attractive.  In other words, the power of beauty capital is so enormous, it exceeds and overcompensates for inherent discrimination.  We, as people, will forgive almost anything if a person is beautiful.
• As uncovered by the economists behind the Freakonomics series, why do heterosexual men secretly consume enormous quantities of so-called “she-male” porn, involving beautiful women with both breasts and a penis, but gay men have virtually zero desire to see the same thing and are turned off by it?  There is something here I’m missing that is the key to understanding a lot about biological drive.  It’s too big, and odd, of a disparity.

For now, this topic needs to go back in the file cabinet and be revisited in future years until it is fully flushed out and concluded.