Sex and Gender 101
- Jun 30
- 3 min read
Rebecca Helm, a biologist and assistant professor at the University of North Carolina, Asheville, US, writes:
Your friendly neighborhood biologist here. I notice many people are discussing biological sexes and gender. Often, biological sex is portrayed as straightforward. Since it’s supposedly simple, let’s explore its biological roots. Let’s discuss sex...
If you have some biology knowledge, you might say that chromosomes determine biological sex: XX for female, XY for male. This is “chromosomal sex,” but is it truly “biological sex”? Well...
It turns out there’s only ONE GENE on the Y chromosome that really influences sex. It’s called the SRY gene. During human embryonic development, the SRY protein activates male-associated genes. Having an SRY gene makes you “genetically male.” But is this “biological sex”?
Sometimes the SRY gene moves from the Y chromosome to an X chromosome. Surprise! Now you have an X with an SRY and a Y without an SRY. What does this imply?
A Y without SRY means you’re physically female, chromosomally male (XY), and genetically female (no SRY). An X with SRY means you’re physically male, chromosomally female (XX), and genetically male (SRY). But biological sex is simple! There must be another explanation...
Sex-related genes ultimately trigger hormones in specific body areas, and cells throughout the body respond to these hormones. Is this the essence of “biological sex”??
“Hormonal male” means producing ‘normal’ levels of male-associated hormones. However, some females have higher levels of ‘male’ hormones than some males. The same goes for ‘female’ hormones. And...
...during development, your body might not produce enough hormones for your genetic sex, leading to being genetically male or female, chromosomally male or female, hormonally non-binary, and physically non-binary. Except cells also play a role in this...
Could cells hold the answer to “biological sex”?? Cells have receptors that respond to sex hormones. But sometimes those receptors don’t function. Like a mobile phone on “do not disturb.” Calls and cells, they won’t respond.
What does all this mean?
It means you could be genetically male or female, chromosomally male or female, hormonally male/female/non-binary, with cells that may or may not respond to male/female/non-binary signals, resulting in a body that can be male/non-binary/female.
Try combining these factors yourself. Notice how complex it becomes? Can you determine the definitive cause of biological sex? Is it fair to judge people based on it?
Of course, you might argue, “Most people are either male or female.”
However, as a biology professor, I’ll tell you...
The reason I don’t have my students examine their own chromosomes in class is that they might discover their chromosomal sex doesn’t match their physical sex, and finding that out during a 10-point assignment is NOT THE RIGHT TIME.
Biological sex is complex. Before discriminating against someone based on “biological sex” & identity, ask yourself: have you seen YOUR chromosomes? Do you know the genes of your loved ones? The hormones of your colleagues? The state of their cells?
Since the answer will likely be no, please be kind, respect people’s right to define who they are, and remember that you don’t have all the answers. Again: biology is complex. Kindness and respect don’t have to be.
Note: Biological classifications exist. XX, XY, XXY, XXYY, and various other variations illustrate why sex isn’t classified as binary. You can’t have a binary classification system with more than two configurations, even if two configurations are more common than others.
Biology is complicated. Be kind to people.
The Path Forward
Join me each weekday at 6 PM Eastern or 3 PM Pacific as I explore and analyze the days news and opinions.
Midday with Cassandra Williamson
On weekdays, usually around 1 PM Eastern.
[The timing is flexible since, as the caregiver for my mom, brother, and sister, my schedule is influenced by their appointments, needs, and situation.]
Programming is available on Social Media.
Comments