How many true genders are there

Intersex: The Redefinition of Gender

This social pressure leads to the fact that a surgical "normalization" of the genital organs is often carried out in DSD. This is undoubtedly a controversial operation, because the operations are often already carried out in infancy and those affected cannot decide for themselves. Randomly assigning a final gender to a child also means grafting a gender on them that they may never get a feel for. Intersex advocates want doctors and parents to wait at least until the child announces their gender (usually around the age of three) or until they can even decide whether to have an operation.

Discussion re-emerged when a lawsuit was filed in South Carolina by the adoptive parents of the child MC in May 2013. MC was born with ovotesticular DSD, conditions in which both ovarian and testicular tissues develop in the genitals and gonads. When MC was 16 months old, the doctors performed an operation in which the child was given a female gender - but the now eight-year-old MC developed more and more towards a boy. Because MC was under government care at the time of the operation, the prosecution alleged not only malpractice but also denial of the fundamental right to physical integrity and procreation. A court ruling last month prevented a trial from taking place at the federal level; the lawsuit against the state continues.

"For children with intersex traits, litigation can be far-reaching," said Julie Greenberg, a gender and sexual legal specialist at the Thomas Jefferson School of Law in San Diego, California. The case will hopefully prevent doctors from having operations in the future if the medical need is still in question, she comments on the case. Perhaps the litigation will lead to a better understanding of what "intersex people go through emotionally and physically when doctors supposedly try to help them fit better into our society," says sociologist Georgiann Davis, who was born with CAIS and is now at university of Nevada is doing research on intersexuality in Las Vegas.

Even if doctors and scientists can empathize with these concerns, the case also shows them how much we still have to learn about the biological causes of gender [19]. In the opinion of many, it is also not enough to simply change medical practice through legal regulations. Instead, they would like to know more about the long-term effects of the operations on the quality of life and sex life of those affected. This is the only way to ultimately decide on the best treatment for people with DSD. Some of these studies have already started.

In the past, the diagnosis of DSD was made through hormone tests, physical examination, and imaging, followed by painstaking analysis of individual genes. With the help of modern genetic methods, several genes can now be analyzed at the same time, so that a genetic diagnosis can be made quickly and the families affected are less stressed. For example, Eric Vilain uses "Whole Exome Sequencing" in XY patients with DSD, in which the protein-coding regions of the entire genome of a person are examined. In 2014, his working group was able to show that the genetic analysis procedure provided a diagnosis with a high degree of probability in 35 percent of the study participants for whom no genetic cause of DSD was known [20].

According to Vilain, Harley and Achermann, doctors are slowly becoming more careful with genital operations. DSD children are now cared for by multidisciplinary teams in order to offer tailor-made treatment and support for both the child themselves and their families. As a rule, however, this boils down to the fact that a DSD child is raised either as male or as female, even if no surgery is performed. Scientists and interest groups agree, according to Vilain: "It can be extremely difficult for a child to grow up with a gender that does not exist in this form." In most countries it is legally impossible to be anything other than male or female.

But if science repeatedly proves different variants of the known genders, then the state and society would also have to deal with the consequences and definitions. Many transgender and intersex activists dream of a world where a person's biological or personal gender is irrelevant. Even if some governments are now moving in this direction, Greenberg remains pessimistic - at least as far as the US is concerned. "It will certainly be difficult to completely abolish the definition of the sexes or to enforce a third undefined gender."

So if the law requires a person to be male or female, should that gender be determined by anatomy, hormones, cells, or chromosomes? And what should be done if the different methods lead to contradicting results? "I don't think there is one biological parameter that covers everything. Ultimately, the gender identity of the individual will therefore be the most sensible parameter," says Vilain. In other words, if you want to know if someone is male or female, it seems best to just ask.

This article appeared under the title "Sex redefined" in Nature 518, pp. 288-291, 2015.