The manner in which societies and cultures have constructed gender and gender identity has been changing for ages. Although an academic or philosophical dichotomy was not acknowledged for several thousand years, the separation of physiology and gender identity has existed perhaps since the dawn of man. It may have its origins in the very moment early hominids forewent stark individualism and entered into John Locke’s social contract. A couple days ago, I had the opportunity to chat with the John L. Loeb Associate Professor of the Social Sciences at Harvard University, Sarah Richardson. Dr. Richardson is a historian and philosopher of science with an impressive collection of research concerning gender and the social dimensions of science. According to Dr. Richardson, the academic sex/gender distinction is traced to the 1960s and sexologists dealing with gender identity disorders or feminist theorists of the same era. Nonetheless, she goes on to trace less specific philosophical sparks of this distinction to the 19th century and earlier.
As we can see, for several decades now, social scientists have been studying countless aspects of gender. The sociology, psychology, history, politics, and performance of gender have been under scrutiny in humanities classrooms around the world. However, one thing that has seemed to remain relatively static is the biological understanding of “sex”, a steadfast counterpart to the fluid and constructed idea of gender. Or so it was presumed. Growing up in the in the fairly progressive time period that I did, my childhood had been at least minimally shaped by the idea that a person’s gender may not actually match up with what they have between their legs. That being said, it was fairly well established that your sex was your sex, and that the distinction was primarily binary (male or female). However, a recent Nature News feature published by Claire Ainsworth examines several studies both new and old, which may complicate the issue of biological sex in the way that the social sciences have unpacked and examined gender. According to Ainsworth, the binary male vs female distinction is antiquated, and biology requires a more comprehensive spectrum.
When I asked Dr. Richardson about this, she elaborated on the concept, explaining how a hard-line distinction between the biological sexes was often an underpinning of more traditionalist ideologies which use this dimorphism to reinforce restrictive gender roles. She feels it is “important to really allow the scientific data to speak for itself and to learn from the great degree of variation…”
But what are these data and wherein lies the variation? We have all heard about individuals born without physiologically distinct male and female parts. In the medical field they are referred to as individuals suffering from Disorders of Sex Development, or DSD, but you might have heard the term “intersex”. These individuals, while not entirely uncommon (some form of DSD occurs in approximately 1% of individuals), are likely not going to rewrite government and medical forms or completely change the way we understand sex. Besides, the fact that many of you will recognize the term “intersex” implies that this condition (or set of conditions) is something that isn’t outside the realm of general knowledge. A lot of us are already aware of intersex individuals, but we’ve yet to adjust our concept of biological sex.
A more broad-scale change in our attitudes toward biological sex may require a more radical challenge. Coincidentally, there are some interesting cellular and molecular events that may give us a little more food for thought. Take, for example, the axiom that human males have one X and one Y sex chromosome in their cells while females have two X chromosomes. This is one of the most universally accepted facts about biological sex, especially among non-scientists. You don’t have to have a degree in a life science to know that this difference in our chromosomes makes us male or female. In the case of this guiding principle of biological sex, there is a good basis for it. It is true in general that if you snatch a single cell from anywhere in my body and look at the chromosomes, you’ll see one X and one Y. However, in the case of the merging of twin embryos, there can be individuals born with some cells bearing an XX and some bearing an XY. Indeed, given certain circumstances of this chimerism as we call it, one may not even notice that they are living with two distinct groups of cells in their body.
Certainly in the case of would-be twins that fuse in the womb, this is an interesting phenomenon. However, chimerism in humans is not so rare. There are a number of much more common processes by which we can acquire the cells of another genetically distinct individual and grow with that person’s cells becoming, quite literally, a part of us. Consider the significant interchanges that can occur between mother and fetus during gestation. These exchanges of materials can and often do include cells, specifically stem cells which are multipotent or pluripotent, a term we use to mean that they can turn into many different kinds of cells. We call this phenomenon microchimerism, and it means that you can have cells from your mother inside of your body right now. In fact, if you have any older siblings, it is possible that their cells continued to grow in your mother’s body, and were subsequently transferred to your body during your growth. I can sense the outcry from younger siblings already. These cells are not just mooching off your energy, either. In many cases, they are earning their keep by working. Cells from your mother or siblings may mature into cardiac tissue, neurons, immune cells, and the like, lending a whole new meaning to the term “you’ve got your mother’s eyes”.
In addition to actually having cells in your body from another person of a different sex, there are instances where the sex differences may be even sneakier. For decades, scientists believed that sex development was a pretty clean switch from female to male, with female being the default program. It was thought that the female programming had to be suppressed by the male programming in order for genes responsible for testes, male sex hormones, and other sex characteristics to win out. However, more recent studies have identified a signal for testicular development which female programming must suppress in order for feminine characteristics to develop. Development of one sex over the other (although expressing them in a binary appears to be getting harder and harder) is not one program overriding the default program. Rather, it is a constant competition of factors. There isn’t just one “yes” or “no”, but rather a chorus of “yes” and “no” shouting in a cacophony that may well come out sounding like a “maybe”.
When I first began researching this issue, these phenomena all seemed like fun or intriguing biological quirks. I thought it was fascinating that some people could be born with genitals not matching their chromosomes or with a cellular makeup that was a mosaic of male and female. However, I began to wonder what these new understandings meant for us as a country, a society, and a species.
One issue, which Ainsworth and many before her have highlighted, is the common practice of genital “normalization” procedures that occur quite frequently. They allow intersex babies to go on and develop as one sex or the other. We have come a long way in our societal treatment of gender. Many people no longer care what pronouns you use to refer to yourself, your choice of sexual partner, and the way you choose to dress. If I am being too optimistic about this, then there are at least signs of progress in that direction. On the other hand, there are no such advances being made in the world of medicine and biological sex. Babies are too young to be able to consent to this change in their genitals, often occurring just days or hours after birth. Do parents have the rights to decide which sex their intersex child continues down the path of? Is this in the same vein as trying to change someone’s sexuality or gender identity? Richards was quick to emphasize that there are clear differences between gential normalization procedures and something like gay conversion therapy. Nevertheless, she underscored that a healthier way to approach this kind of surgery would be to ensure it is coming from a place of informed and empirical science, perhaps for individuals who are old enough to understand what is unique about their bodies, and not out of our sense of panic that intersex does not conform to the binary.
Another issue may arise in individuals with chimerisms, which may describe many of us. There are certain diseases, both genetic and acquired, which affect one sex (or perhaps I should say “chromosomal profile”?) more severely than the other. Let’s say that certain cells in my brain developed from my mother’s cells which I acquired in the womb. If I were suffering from a brain disease affecting XX individuals more severely than XY individuals, doctors might not necessarily diagnose me correctly until they had exhausted many other options, simply because I’d checked M on the form in the waiting room.
It would appear that the issue of sex development and biological sex has not quite reached a critical mass, but this growing body of work certainly complicates sex in ways we could not have anticipated during the development of our medical system and our societal opinions on sex. While pressure to adhere to a given gender is beginning to alleviate, pressure to conform to a single, specific sex is alive and well. It can be a little discomforting to think so differently about a concept we often consider black and white, but understanding the intricacies which govern sex development can help us to appreciate the beauty of gray.