Rethinking Transgenderism

Rethinking the Conservative Approach to Transgenderism
by Jennifer Gruenke
within Bioethics, Science
July 29th, 2015
2223 128 2396
Conservatives do not take the introspective reports of transgendered people
seriously, but there are good scientific reasons for supposing that subjective
experience of gender is legitimate, even when it contradicts apparent
biological sex.

Transgendered people—people who appear to be one sex but report the
experience of being the other—have been in the news lately. The
conservative reaction to this phenomenon is, in some respects, puzzling.
Conservatives do not take these introspective reports seriously; they believe
that people seeking sex-change operations (now more often referred to as
sex-reassignment surgeries or gender-affirming surgeries) are almost
uniformly confused. Their approach to transgendered people is often polite,
even compassionate, but always firm in the conviction that transgendered
people are mistaken.

Now, subjective experience is often, but not always, reliable. In this case,
there are good scientific reasons for supposing that subjective experience of
gender can legitimately diverge from the sex of one’s reproductive organs,
so conservatives should be cautious in accusing transgendered people of
confusion. To show why this is true, I will show that developmental biology
demonstrates that there are multiple pathways of sexual development, that
one of those pathways is in the brain, and that the pathways of sexual
development can diverge from one another.

I will follow the convention of using the word “sex” to refer to the sexual
characteristics of the body exclusive of the brain, and “gender” to refer to
the subjective, internal experience of being a male or female. Sexual
characteristics are either primary or secondary. Primary sexual
characteristics develop prenatally and directly relate to reproduction (for
example, having testes vs. ovaries). Secondary sexual characteristics develop
at puberty, and may or may not relate to reproduction. For example, breast
tissue in females may eventually provide food for an infant, whereas facial
hair in males does not contribute to reproduction. The biological categories
of female vs male sexual characteristics are defined empirically. That is,
most babies with male primary sexual characteristics go on to develop a
particular set of secondary sexual characteristics.

Sex can be male, female, or in rare cases, somewhere in between, and can be
analyzed scientifically. As I will explain, gender appears to depend strongly,
but not exclusively, on the brain. Analysis of the brain can allow an outside
observer to make a reasonable, albeit imperfect, guess about a person’s

Mismatched Pathways of Sexual Development
Except in cases of monozygotic twinning, humans reproduce sexually. This
requires some individuals to be male and others female. The biological
triggers for an individual to be either male or female vary from species to
species. For most mammals, including humans, females usually have two X
chromosomes; males usually have an X and a Y chromosome. But for birds,
this situation is reversed, and for many species of reptile, sex is determined
by egg incubation temperature. Therefore differential sexual development in
the animal kingdom is not reducible to a common physical trigger.
Furthermore, some species, such as the clownfish, can change their sex over
the course of their lifespan. Thus it is a mistake to think of the sex of an
individual organism as fixed in every case for every species.

Humans, of course, are not fish, and we don’t observe our fellow humans
undergoing a natural change from one sex to the other. But individual
humans do go through a stage of development in which we have both male
and female physical parts at the same time. At about six or seven weeks of
development, a human embryo clearly has a human body. It has a head with
eyes and a torso with limbs. Fingers and toes are beginning to develop but
have not yet separated. Internal organs like the heart, brain, and liver are
present, if incompletely developed. Not surprisingly, given that these other
organs are well into their development, the reproductive organs are
developing, too. But instead of an incompletely developed version of either
male or female reproductive structures, the embryo has both. It has one set
of tubules that can develop into the uterus, fallopian tubes, and the upper
third of the vagina, and another that can develop into a series of tubules that
transport sperm. The gonads are also present, and can develop into either
ovaries or testes.

As the human embryo moves forward from this bipotential state, the default
developmental pathway is female. The Y chromosome normally initiates a
number of different pathways that inhibit the development of female
structures, instead masculinizing the gonads, genitals, and brain. It is
possible to have a mismatch between chromosomal sex and bodily sex. For
example, in cases of the intersex condition called complete androgen
insensitivity syndrome (CAIS), a human with XY chromosomes develops
into a girl due to the lack of androgen receptors; the androgens (testosterone
and others) that are present cannot affect their development. At puberty,
these girls develop physically as women and have a female gender identity.
They typically look even more feminine than XX women, who, at least, are
sensitive to the small amounts of testosterone that they have.

Their condition may not be discovered until they fail to menstruate as
teenagers. They have no uterus and have testes rather than ovaries. In this
case, the pathways of sexual development were mismatched. The male
pathway was activated for the gonads and the embryonic structures that give
rise to the uterus, but the female pathway was activated for the brain and
external genitalia.

Women with CAIS are easily diagnosed as intersex in early adulthood, but
more subtle types of intersex conditions might go unnoticed. In one case, the
XY karyotype of a fetus was determined during a check for chromosomal
abnormalities. But at birth the baby turned out to be a girl with normal uterus
and ovaries. It appears that in her case, all of the pathways of her sexual
development were female, due to a mutation that affects them all. If she had
not had her chromosomes tested, she might not ever have known that she is

Sexual Development of the Brain
So what do intersex conditions have to do with being transgender? One of
the pathways of prenatal sexual development is in the brain. There is good
evidence that babies are born with predispositions to consider themselves
male or female, that is, to have a gender. Some male infants who lose their
genitalia in accidents have been reconstructed as girls, with little success.
That is, they often grow up to experience the same thing that transgendered
people experience—their perception of their own gender does not match
their apparent sex.
Further evidence that infants are born with a predisposition towards a gender
is seen in cases of an intersex condition called 5-alpha reductase deficiency
(5-ARD). In 5-ARD, chromosomal males lack the hormone that
masculinizes the genitals, so they appear to be girls. But in most cases, the
child will identify as a male, despite being born with female genitals and, for
that reason, being raised as a girl. It appears that testosterone masculinizes
the brain, but not the genitals, during male embryological development.
Individuals with such a mutation end up with some parts of the body (testes,
brain) masculinized but others (genitals) following the default female

Other data support the conclusion that transgenderism has a genetic basis;
there is a strong concordance of occurrence among identical twins, but not
among fraternal twins. That is, if one identical twin is transgender, then, in
more than a third of cases, the other will be, too. Although we might expect
concordance to be higher, there is precedence for identical twins with
intersex conditions in which one twin is more severely affected than the
other. Because identical twins live in similar environments, we might think
that some of the concordance is due to shared environment. But fraternal
twins also share environment, and the study that found strong concordance
for identical twins found no concordance at all for fraternal twins. Human
neurology is complicated.

Thus gender appears to be influenced by genes but not absolutely
determined by them. Specific mutations leading to transgenderism have not
been discovered, but that is what we’d expect considering its rarity; one
report from Sweden, where transitioning from one sex to the other is
relatively well-accepted, shows that over 30 years (1972-2002), only 0.006%
of the population over age fifteen requested sex reassignment.

Possibly Reliable Introspection
If we put the pieces together, we know that there are multiple pathways of
sexual development and that they are not all regulated together. One
pathway is the development of the gonads into either ovaries or testes;
another is the development of external genitalia, and another is the
development of the brain to be predisposed toward one gender. We know
that the gonads and external genitals can differ from each other, and that
both can differ from chromosomal sex. So we ought to expect to find
individuals whose brain pathway differs from the other pathways. Given the
mutation rate, the size of the genome, and the number of humans in the
world, if a molecular pathway can be mutated without killing the individual,
the mutation will most likely show up in someone. And I would predict that
people with such a mutation would look just like cases of transgendered

Consider a case study of a genetic male with normal male genitalia who,
since childhood, has had the first-person perception of a female identity. It’s
possible that this is a case of confusion about identity rooted in
psychological trauma. But it’s also possible that this person has some
mutation that prevented the masculinization of the brain. The biology leads
us to expect that there will be some people in the latter category, even if we
don’t currently have a genetic test to identify these people. On the other
hand, psychologists do have some ability to identify trauma-induced identity
disorders, so in the meantime it’s possible to eliminate people from the
former category. We might first look for signs of dissociative disorders or
schizophrenia, for instance.

But unless such disorders seem to be the problem, isn’t it most likely that
this individual has some intersex condition, one in which the brain does not
match genetic sex, in a way that is—currently—only discernible through
introspection? Given how little is known about these rare cases, a high
degree of certainty is not possible, but inference to the best explanation
seems to warrant this conclusion.

To be sure, our subject would still be a genetic male with Y chromosomes in
the brain cells. But absolute reduction of sex to the sex chromosomes is not
supported by the biology, for as we have seen above, with the right mutation,
one could have a Y chromosome but an otherwise unambiguously female
body, including ovaries and uterus. For that reason, chromosomal
reductionism is an unacceptable account of sex.

An Objection
Now, it is worth considering a more principled objection from the
conservative front. Some might contend that, if we accept first-person
accounts with respect to gender identity, we will have no principled reason
to reject them in other cases. For instance, the first-person report is
unreliable in the case of anorexia.

An anorexic person is convinced that she is overweight, even when she is
already underweight. This, it might be claimed, is analogous to the case of a
transgender person. A transgender person might sincerely believe that he is
female, but that does not mean that he is not mistaken. Indeed, the objector
might press that brain chemistry cannot solve this problem. For suppose that
an anorexic person does have the brain chemistry of an overweight person,
and this similarity is accountable in terms of genetic factors; in such a case,
we would not say that the girl really is overweight, despite appearances.
We’d say that she is really underweight, personal conviction
notwithstanding. Anorexia just is a condition characterized in terms of a
desire to be thin in spite of already being thin; her brain chemistry and
emphatic beliefs don’t defeat this. Moreover, the anorexic person is not
correct merely because her reports match her brain and indeed her brain (if
not the rest of her body) developed along pathways characteristic of
overweight people. Why, our objector continues, can’t a transgender person
be similarly mistaken? The fact that a transgender person is making reports
in line with her neurological development does not establish that she cannot
be incorrect.

But the analogy between people who are anorexic and those who are
transgendered breaks down when we consider the respective goals of the two
relevant parts of the brain. The part of the brain that regulates body weight
exists so that a healthy weight can be maintained. There is a range for
healthy body weight that is the norm; someone with anorexia wants to
achieve a body weight that will lead to electrolyte imbalances that can be
fatal. Thus in anorexia, subjective perception is clearly at odds with proper
function of the human body. On the other hand, the part of the brain that
contributes to the perception of gender doesn’t regulate anything, but exists
just for psychological identity. One can survive, and even reproduce, without
having any gender identity at all.

I am not arguing that introspective reports of sex are infallible. But
according to some studies, a majority of people who undergo sex
reassignment surgery are happy with the decision. There is a real danger of
misdiagnosing someone as transgender and doing surgery that does them
harm, and conservatives have been correct to raise this concern in the face of
those who are prepared to affirm every request. In giving the impression that
this is a decisive reason against every desired sex-reassignment surgery,
though, some conservatives have overstepped. Trying to change a legitimate
self-perception of gender also does harm.

Jennifer Gruenke is professor of biology and director of the Hammons
Center for Scientific Studies at Union University.