1. This affidavit is provided by Professor Louis
Gooren of the University Hospital of the Vrije Universtiteit of Amsterdam, the
Netherlands.
2. Born in 1943, I am a medical doctor
specialising in the field of endocrinology. Within this field, diseases
related to disorders of sexual differentiation and the biological process of
becoming man or woman are the focus of my work. In 1988 I was appointed
Professor and assigned to the treatment of patients who present with gender
identity problems as well as other patients with sexual differentiation (intersex)
disorders who need hormonal and surgical medical interventions. Over the past
24 years I have worked at the Gender Clinic of the University Hospital, which
receives about 150 new patients per year. Approximately 80-90 of them receive
actual hormone and surgical therapy. I have published extensively on these
subjects and enjoy wide and international professional recognition. I have, by
invitation, contributed to text books of medicine on these subjects. In recent
years Institutions of the Council of Europe have called upon me to provide
expertise in the area of gender problems.
3. Gender Identity Disorder (transsexualism)
is a medical condition and from my work and other research in this area I now
believe that transsexualism is a disorder of sexual differentiation: the
process of becoming man or woman as we conventionally understand it.
4. Traditionally it is assumed that sexual
differentiation, the process of becoming man or woman is completed with the
formation of the external genitalia, the criterion used to assign a new-born
child to the male or female sex. From the beginning of this century it became
clear in laboratory animals that this is not the endpoint of the sexual
differentiation process but that also the brain undergoes a sexual
differentiation into male and female, largely predicting/correlating with
future sexual and non-sexual behaviour.
5. The process of sexual differentiation
takes place in distinct steps, first the chromosomal configuration is
established, next Gonadal differentiation, next differentiation of the
internal and external genitalia and finally the differentiation of the brain
into male or female.
6. Normally all steps in the process of
sexual differentiation are concordant (in men, an XY chromosomal pattern,
testis, male internal and external genitalia and a male brain differentiation
being the substrate of male type behaviour; in women, an XX chromosomal
pattern, ovary, female internal and external genitalia and a female brain
differentiation being the substrate of female-type behaviour).
7. It is remarkable that in some mammalian
species this process of brain sexual differentiation takes place after birth.
Swaab and Hofman have shown that one brain structure, that is different
between men and women, becomes only sex-dimorphic between the ages of two and
four years, well after birth and long after assignment to the male or female
sex has taken place. Nature is not free of errors and the process of sexual
differentiation is no exception. There are human beings in whom not all
traditional criteria of sex are concordant. They may have some biological
characteristics of one sex and some of the others, a condition known as
intersexed.
8. The human condition requires that new-borns
are assigned to one sex or the other. The social and the legal system has left
no room for intersexed subjects. If a new-born child presents with an
intersexed condition a medical decision must be made to assign this baby to
the male or female sex. It is now a generally accepted medical practice to
assign an intersexed new-born to that sex in which the unlucky child, on the
basis of medical expertise and reasonable expectation, will function best. It
is of note that biological characteristics are not imperative in this decision
process. The decision is based on prognosticated future sexual and nonsexual
functioning. The legal system registers these new-born children in accordance
with the medical decision. Thus, it is no longer tenable to claim that the
genetic or gonadal criterion determines one’s status as male or female.
9. Some intersex conditions are such that
they can not even be determined at birth and are only discovered much later at
puberty. As such some of our fellow human beings live (unbeknown to all but
their medical practitioner) their lives as women but with a male-type XY
chromosomal pattern or testis and vice versa.
10. Sexual and nonsexual brain
differentiation is now accepted as part of the process of becoming male or
female in the mammalian species to which humans belong. In animal
experimentation it is easily possible to induce a female type of sexual and
nonsexual behaviour in animals that have, up to that final stage of sexual
differentiation, a completely male pattern and vice versa. Depending on the
type of manipulation applied in the animal experiment, in-between types of
behaviour can also be observed. On the basis of the findings of these
experiments it has been hypothesised that in human subjects with gender
identity problems the sexual differentiation of their brains has not followed
the pattern predicted by their earlier steps in the sexual differentiation
process (such as chromosomes, gonad, genitalia) but has followed a pattern
typical of the opposite sex in the final stage of that differentiation
process; as indicated above, a situation that can be induced in laboratory
animals by experimental manipulation.
11. Generalisations of biological principles
between the different members of the mammalian species must be done with
caution, but they cannot be totally dismissed. Medicine has progressed
enormously by animal experimentation using this extrapolation from other
mammalian species to the human. The validity of extrapolation of the sexual
differentiation process of the brain in other mammals to the human has been
corroborated by findings of anatomical and functional brain differences
between males and females, including the human species. The collection of data
in the human has been, and is, still slow due to obvious ethical restrictions
on collecting brain material for research.
12. Interestingly, Zhou, Swaab, Gooren &
Hofman, published in 1995 a scientific report that could demonstrate that in
one of the human brain structures that is different between men and women, a
totally female pattern was encountered in six male-tofemale transsexuals. They
were able to show that this was not due to the transsexuals’ previous
cross-sex hormone treatment. These findings showed that a biological structure
in the brain distinguishes male-to-female transsexuals from men. The findings
were published in the leading scientific journal (Nature) with a rigorous
scientific review process which would not have overlooked essential scientific
biases in the design and interpretation of the experiment.
13. In conclusion: Since there is evidence
that the sexual differentiation of the brain in the human occurs (also) after
birth it is unavoidable that in subjects with errors of the sexual
differentiation of the brain, sex assignment takes place after birth,
sometimes much later in their lives since it requires a large amount of life
experience to discover the predicament of being born in the wrong sex: in
other words having sexual and nonsexual brain patterns that are in
contradiction with the other sex characteristics.
Like other people afflicted with disorders in
this process of sex differentiation, transsexual people need to be medically
rehabilitated so that they can live acceptable lives as men or women. This
decision is not essentially different from the one made in cases of intersexed
children where assignment takes place to the sex in which they in all
likelihood will function best. In the case of a intersexed child it is often
possible to tell at birth that the sexual differentiation process has not
taken place in a conventional way and so it is possible to make that decision
to assign a sex through medical intervention shortly after birth... The
decision to recommend hormonal and surgical treatment for a transsexual person
takes place much later in life and is based on the conclusion of a thorough
psycho-diagnostic process that concludes that a disorder has occurred in the
process of sexual differentiation and that the person will benefit from
hormonal and surgical sex assignment. There is never any disagreement that the
expenses of sex assignment at that stage are to be borne by the relevant
health insurance.
Citation: This expert
witness affidavit has been provided to the High Court in the Case of Elizabeth
Bellinger (see page 39, Appendix 4 of “Recognising the Identity and Rights
of Transsexual and Transgender People in the United Kingdom”, Press For
Change 1999).
