Battle of the Sexes
In a recent discussion about gender identity, gender roles, and the general move towards a more accepting society I mentioned the concept of “Two-spirit” in Native Northern American culture. Once I got thinking I started reading, and in my exploration of texts about gender and culture, I have come across a wonderful world of diversity and history.
Across the globe and throughout history the concept of multiple genders and their importance is prolific; even Plato theorised that a third gender has been lost in time. Sadly, I came across a lot of angry trolls along my journey too. There are some people who seem to believe that their opinions are fact and any deviation from their normal is abhorrent. One of the arguments these people routinely use to try to put down transgender and non-binary people is “there are only two sexes”. Not only does this completely side-line any conversation about the difference between gender and sex, but it is also just plain wrong.
The Majority of humans are born with 46 chromosomes in 23 pairs. The 23rd pair is known as the Sex chromosomes which are X and Y. The most well-known sexes are Female XX and male XY, but people can be born with different forms of these two chromosomes, and different numbers of these chromosomes. Furthermore, sex is not determined solely by which chromosomes are present, but by hormonal balances and phenotypic variations.
Aneuploidy, the presence of an abnormal number of chromosomes in a cell, can occur in several different survivable conditions. It is important to remember that not all Aneuploidy conditions are intersex, several of these conditions are considered to be Male or Female. For example, Turner’s syndrome (Sybert and McCauley, 2004) is the only survivable form of only having a single-sex chromosome. Turner’s syndrome describes females who have one X chromosome and little or no second sex chromosome.
Another Female aneusomy condition is triple X syndrome (Otter et.al, 2010), wherein three X chromosomes are present; this addition of X chromosomes are seen in four X and five X. These syndromes can either have little effect on the female or can cause developmental delays and physical anomalies. Furthermore, XXYY karyotype is similar to tetra X in females, but is found in males and causes more distinct characteristics (Blumling et.al., 2020). Males can also be born with XXY karyotype.
Broadly speaking, there are three main intersex groups, which are grouped by the presence of gonads. “Female pseudohermaphrodites”: the presence of only ovaries, but with some aspects of male genitalia; “true hermaphrodites” who possess both ovary and testy; and “male pseudohermaphrodites”, describing the presence of only testes, but with some aspects of female genitalia. All of which can be controlled by sex chromosomes, hormonal expression, and gene expression. Blackless et.al (2000) even noted cases of hermaphrodity being passed through family lines suggesting that there are genes involved in the sexual determination that are not present on the sex chromosomes but on other chromosomes.
Androgen insensitivity syndrome (AIS) is a well-known sexual ambiguity disorder (Hughes et.al., 2012). Here individuals are “genetically male” in that they have XY karyotype and testes however, their genitalia is not typically male. There are two types of AIS, complete androgen insensitivity syndrome (CAIS) wherein genitals are entirely female, and partial androgen insensitivity syndrome (PAIS) the genitals are between male and female. AIS is a form of male pseudo hermaphrodity caused by the body not reacting properly to the hormone androgen and therefore presenting female. Other forms of male pseudohermaphroditism are known as “Guevedoces”, this form presents similarly to AIS, however at approximately 12 years of age Male genitalia forms, this is due to 5-alpha reductase deficiency, the enzyme involved in male outer genitalia development, and is common in the Dominican Republic (Moisei et.al., 2019).
I could go on and delve further into countless more sex variants in humans, but I think you get the picture…
Sources
Sybert, V.P. and McCauley, E., 2004. Turner's syndrome. New England Journal of Medicine, 351(12), pp.1227-1238.
Otter, M., Schrander-Stumpel, C.T. and Curfs, L.M., 2010. Triple X syndrome: a review of the literature. European Journal of Human Genetics, 18(3), pp.265-271.
Blumling, A.A., Martyn, K., Talboy, A. and Close, S., 2020, June. Rare sex chromosome variation 48, XXYY: An integrative review. In American Journal of Medical Genetics Part C: Seminars in Medical Genetics. Hoboken, USA: John Wiley & Sons, Inc..
Blackless, M., Charuvastra, A., Derryck, A., Fausto‐Sterling, A., Lauzanne, K. and Lee, E., 2000. How sexually dimorphic are we? Review and synthesis. American Journal of Human Biology: The Official Journal of the Human Biology Association, 12(2), pp.151-166.
Hughes, I.A., Davies, J.D., Bunch, T.I., Pasterski, V., Mastroyannopoulou, K. and MacDougall, J., 2012. Androgen insensitivity syndrome. The Lancet, 380(9851), pp.1419-1428.
Moisei, C., Lesnic, A., Sima, R.M., Bălălău, C. and Pleș, L., 2019. MALE PSEUDOHERMAPHRODITISM: CASE REPORT. Romanian Journal of Clinical Research, 2(1), pp.55-58.
Written by Libby Bowles
I’m a PhD Researcher at Prifysgol Aberystwyth, studying the perenniality syndrome in Grasses. I’m passionate about public engagement in science and the sharing of knowledge regarding the world we live in, especially the weird and wonderful