Expert Witness Statement – Prof. L. Gooren

Expert Witness Statement

Prof. L. Gooren
[Abstract] Full Text [PDF]

Prof. Louis Gooren

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).