An Introduction to Genetic Sex
Your genetic sex is affected by genetic differences or variations in fetal development. There are f*ck-ton of genetic combinations that further prove the unreliability of the gender binary as a means of social categorization–more than just “male” and “female” like your eighth-grade science teachers want you to believe. While gender exists on a continuum, sex exists on a biological spectrum.
As many as 1 in 100 people have disorders or differences of sex development (DSD) or is intersex. These differences begin in the womb: each embryo starts out with a pair of primitive organs (called proto-gonads) that develop into male or female gonads at about six to eight weeks. Sex differentiation is usually set in motion by the SRY gene on the Y-chromosome that changes the proto-gonads into the testes. The testes then secrete androgens (the male hormones) and the fetus develops a prostate, scrotum, and penis. Without the SRY gene, the proto-gonads become ovaries that secrete estrogen and the fetus develops female anatomy (uterus, vagina, and clitoris). The SRY gene, however, may function differently than others’ and lead to an XY embryo that fails to develop male anatomy and is identified at birth as a girl–or, it might show up on the X chromosome, leading to an XX embryo that develops male anatomy and is identified at birth as a boy.
“An intersex person’s anatomy is different than what society expects. A person might look female on the outside, but have mostly male organs on the inside. Or a person might have sex chromosomes that are different than expected. Intersex persons may have genitals that differ from what society expects. For instance, an intersex person might have a penis that is a lot smaller than usual. Or a clitoris that is a lot larger. Sometimes a person has a combination of both parts. Sometimes parents have children undergo surgery to bring their genitals into alignment with society’s expectations. That means the parents and doctor must make a guess at what sex the child or infant would like to be. This is usually done before children can fully understand the implications of the surgery.” Source
Genetic variations might occur that are unrelated to the SRY gene, such as CAIS, complete androgen insensitivity syndrome in which an XY embryo’s cells respond minimally, if at all, to the signals of male hormones. Even though the proto-gonads become testes and the fetus produces androgens, male genitals don’t develop. The baby “looks” female with a clitoris and vagina and is often socialized as a girl. People with CAIS have Y chromosomes and internal testes but their external genitalia are female and they develop as females at puberty.
Some of the more common causes for these differences are the 5-alpha-reductase deficiency, differences in the SRY gene, and variations in the CAIS gene. Someone with a 5-alpha reductase deficiency is genetically male (with one X and one Y chromosome) with testes. However, their bodies do not produce enough dihydrotestosterone (DHT), a hormone that is critical in male sex organ development before birth. Many people with this deficiency are born with external genitalia that is ambiguous (not clearly male or female), “looks” female, or appears predominantly male as is the case with micropenises or urethra openings on the underside of their penis. Children with this condition are often raised and socialized as girls, often in conjunction with surgical genital modification during infancy–an irreversible procedure that is medically unnecessary.
Other conditions, like congenital adrenal hyperplasia, are less noticeable and are only discovered by accident. For example, in 2014, surgeons reported that they had been operating on a hernia in a man when they discovered that he had a womb. The man was 70 and had fathered four children.
There is no simple dichotomy between biological sexes–sexual differentiation results from the influence of many genes, not one female gene and one male gene. This is especially apparent in light of new scientific discoveries at the cellular level:
“What’s more, new technologies in DNA sequencing and cell biology are revealing that almost everyone is, to varying degrees, a patchwork of genetically distinct cells, some with a sex that might not match that of the rest of their body. Some studies even suggest that the sex of each cell drives its behaviour, through a complicated network of molecular interactions.” Source
For example, some people have mosaicism which occurs when they develop from a single fertilized egg but become a patchwork of cells with different genetic makeups. This can result in identical twins of different sexes. Other people have chimaerism, where a person develops from a mixture of two fertilized eggs, or microchimerism, a common occurrence during which stem cells from a fetus cross into the parent’s body through the placenta and vice versa. This often results in “female” parents carrying “male” genes.
So what does all this mean? It means that the sex and gender binary are, quite frankly, BS. These strict sexual dichotomies only exist to divide a ruling class from a subordinate one within a systemic patriarchal culture. The once-harsh dividing line between what is male and what is female is blurrier an ever, and biological sex can (and should) be defined in a number of different ways–which is a step in the right direction.
Other Sources
https://sexetc.org/info-center/post/what-does-intersex-mean-is-it-the-same-as-hermaphrodite/
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