With new improvements in gene-editing and sequencing technology, there is potential for preventing, diagnosing, treating and even curing previously intractable diseases. There is also the exciting possibility of applications beyond medicine. Many are trying to use these technologies to explain complex human behavior and personality traits in genetic terms. While this kind of research could help us better understand ourselves, studies looking for genetic causes of stigmatized traits such as non-conforming gender identities may also further stigmatize the groups being studied.

A review of the genetic basis of gender identity published in the journal Behavior Genetics in 2018 sets an example for the socially responsible publication of scientific findings. The authors wanted to “provoke thoughtful consideration of the crucial role that human genetics can play in making society more open and equitable for gender minorities.”

This means that differences in gender identity can be explained at least partly, but not completely, by genetic differences.

Gender identity (our internal sense of how we relate to cultural gender norms) is distinct from gender expression (our outward presentation) and gender roles (how genders are expected to behave). Gender identity doesn’t always align with sex (the biology of our chromosomes, hormones, and genitalia), in which case a person may be transgender. Drawing on results from 11 twin-based studies, the researchers examined how much variation in gender identity and gender-related behaviors can be explained by differences in genetics – a measure known as “heritability.” While heritability estimates varied widely between studies and age-groups, the review concluded that heritability of gender identity is comparable to other behavioral and personality traits, generally between 30% and 60%. This means that differences in gender identity can be explained at least partly, but not completely, by genetic differences. Some of the remaining variation can be attributed to unique environmental factors, like life experiences that differ from person to person.

The scientists propose that, like other complex traits, many genetic variants contribute to gender identity through interactions with other genes and environmental factors, but do not determine the trait on their own. While other researchers have tried to identify some of the variants in this intricate network, many findings have been inconsistent, and sample sizes are often small and exclude non-binary gender identities. No single genetic difference can be used to predict your gender identity. By this model, gender identity is a continuous, non-binary spectrum – something gender diversity advocates have been saying for years.

Zachary Drucker, The Gender Spectrum Collection

The authors appropriately acknowledged that transgender and gender non-conforming identities have historically been treated as medical conditions that need to be fixed, rather than as healthy, valid ways of being. For example, it took until 2013 for gender identity disorder to be removed as a mental disorder from the widely used Diagnostics and Statistics Manual (DSM-5) and until 2019 for the World Health Organization to follow suit in the International Classification of Diseases (ICD-11). Pathologization has fueled societal stigma and been used to justify discrimination. The gender identity and/or gender expression of transgender people is still criminalized by fourteen countries. The damaging pseudoscientific practice of conversion therapy aiming to “cure” LGBTQIA+ individuals of their identities is also legal across most of the world. A 2015 survey of transgender people in the United States revealed that this population is disproportionately affected by depression, poverty, unemployment, workplace discrimination, and mistreatment when seeking health care.

....people may weigh the genetic effect more heavily than the evidence justifies due to its seemingly “immutable” quality, downplaying the effect of other influences.

For the general public, the majority of information about genetics comes from the mass media, like news coverage of scientific research, TV shows, movies, and advertising. Unfortunately, genetic concepts are often heavily oversimplified for the sake of catchy headlines or convenient plot devices. This oversimplification can lead to genetic essentialist biases – the view that human behavior and identity is unchangeably and inescapably defined by genes. According to this view, if you have a variation of a particular gene, you will inevitably exhibit a particular trait. This could relate to your appearance, health, personality, or behavior. With this bias, even if it is reported that gender identity is affected by both genetics and environment, as found in the Behavior Genetics review, people may weigh the genetic effect more heavily than the evidence justifies due to its seemingly “immutable” quality, downplaying the effect of other influences.

This simplified view can be dangerous. Some studies show that the more someone sees gender as caused by differences in people’s genes, the more likely they are to perceive greater differences between genders. This could potentially reinforce the harmful misconception that traits like gender are binary – that a person can be a woman or a man and nothing else. In some cases, an essentialist mindset is associated with sexist or racist views. Research on genetic differences between races can encourage the belief that there are important essential differences between races, a tenet that is uncomfortably similar to those that fueled eugenic practices, such as the early 20th century U.S. marriage restrictions imposed upon interracial couples and the “mentally deficient” as well as the legalization of forced sterilization. These U.S. laws provided a template for Hitler’s systematic extermination of “undesirables.”

Zachary Drucker, The Gender Spectrum Collection

Eugenic practices are still employed today. Transgender people are required to undergo sterilization to achieve legal recognition of their gender in Japan and many European countries. These laws are based on the flawed premise that gender non-conforming people are mentally ill and unfit to raise children. In my own state of Victoria, Australia, it wasn’t until earlier this year that a bill was passed to remove sex affirmation surgery from the list of requirements to change a birth certificate to align with a person’s gender identity. Other Australian states still have this requirement. Given this ongoing history of stigma, the risks and benefits of genetic studies should be carefully evaluated.

Interestingly, a survey assessing attitudes towards genetic research on LGBTQIA+ identities shows that these studies can sometimes have benefits. In this study, which has not yet been peer-reviewed, people with the lowest tolerance of queer identities and behavior self-reported that they would become more accepting if a biological basis was found. Among the most accepting of responders were people who believe that science contributed to their greater acceptance of LGBTQIA+ identities. This suggests that genetic studies could pave the way towards reducing stigma and also provide validation, supporting “born that way” arguments. Yet understandably, some non-cisgender responders were concerned about such research – we have the most to lose if results are misconstrued or wielded against us.

...the number of studies looking for explanations of human behavior in our genomes will only grow – regardless of their necessity or value

Regardless, we need to step away from the fatalistic view that genetics define every aspect of ourselves. The idea that a gene can give you an unchangeable behavioral trait is at odds with the fluidity of gender and sexuality. And, as the Behavior Genetics review shows, behavioral traits are influenced by far more than genetics. Embracing the complexity of these traits is consistent with a values system that allows everyone, LGBTQIA+ or not, to present and exist anywhere on the relative spectra that makes sense for them.

Given the unstoppable curiosity of humanity and the exciting technologies at hand, the number of studies looking for explanations of human behavior in our genomes will only grow – regardless of their necessity or value. Researchers have a responsibility to consider how their research may impact the communities they are studying as complex results can easily be misinterpreted or abused. Scientists need to engage with members of the relevant communities at all stages of research – all the way from study design to publication and beyond – if they are to answer scientific questions that are meaningful to both parties.