In view of the uninformed opinion expressed by some of the members of the House of Lords and the House of Commons during the debates on the Gender Recognition Bill, the following document was sent out, from my office, to all members of the House of Commons Standing Committee on the Bill prior to the Committee stage (2004). It was prepared to promote the understanding that gender dysphoria is not a mental illness, and to explain, briefly, something of the extreme complexity of natural variation in the field of sex differentiation, of which gender dysphoria forms a small part. Dr Lynne Jones MP. PhD.
Transsexualism: The Inside Story – Information for MPs
Atypical gender development may give rise to a psychological experience of oneself as a man or as a woman, that is, a gender identity, which is incongruent with the phenotype (the sex differentiated characteristics of the body). Individuals experiencing this condition will have been raised, from birth, in the gender role (the social category of boy or girl) which is consistent with their phenotypic appearance. In some cases, both the appearance of the body and the associated gender role give rise to great discomfort. The personal experience of this severe gender variance is sometimes described medically as gender dysphoria.
This condition may be experienced in varying degrees, but in its profound and persistent form, individuals may need to ‘transition’, to live in the gender role which is consistent with their core gender identity. Individuals experiencing this condition may be referred to as trans men (those assigned female at birth who identity as men, and who may ‘transition’ to live as men) and trans women (those assigned male at birth but who identify as women and who may transition to live as woman).
This man/woman divide is described as a ‘binary’ model. However, there are also wide variations in identity, that are ‘non-binary’. In this varied group there are many self-descriptions, and unusual pronouns, and new titles may be invented. Being trans is not the same as cross-dressing (transvestism) which is temporary and not necessarily associated with gender dysphoria. There is some overlap, however, as some people who eventually transition , have spent many years cross-dressing in safe places. It should be noted that issues of gender identity are not the same as sexual orientation, which is about whom you are sexually attracted to.
‘M’ or ‘F’ is entered on the birth certificate in accordance with genital appearance at birth.
The process of sex differentiation is initiated in the fetus in the early stages of pregnancy. Typically, this differentiation is associated with the chromosomes: all fetuses have an X chromosome; the second chromosome in a boy will be Y, and in a girl will be X. Certain genes on the Y chromosome trigger the cascade of masculinising hormones from the testes (androgens – testosterone and MIH, a hormone antagonistic to female internal genitalia) which move the fetus from its female (default) status towards the male status.
Differentiation of sex characteristics: genitalia, gonads (testes/ovaries) and of the brain, and the apparently binary male or female outcome in all these areas is, therefore, driven by the genes and the hormone environment – especially the presence or absence of testosterone. The latter depends partly on the pregnant mother and partly on the hormone (endocrine) system of the fetus itself.
It is assumed that the baby’s development is consistent, that all the sex characteristics will be congruent with each other, and that a child assigned as male will identify as a boy, and that a female infant will identify as a girl. This assumption is – usually – accurate.
However it is not always so; by the time of birth, approximately 1 in 100 babies will have developed conditions known generally as intersex or disorders of sex development. These arise where there is some degree of sex or gender anomaly, owing to a disturbance in the genetic code and/or the hormone environment impacting on the process of sex differentiation.
The possible anomalies are many and varied. There may be visible ambiguities of the genitalia so that the assignment of the baby as a boy or girl is problematic; there may be inconsistencies between genitalia and gonads, and/or internal reproductive organs. In some cases, where the fetus is insensitive to the masculinising influence of androgens, an individual may develop as a phenotypic girl despite having XY chromosomes. However, she will have undescended testes, no uterus or ovaries and a short, or more-or-less non-existent, vagina.
So, incongruence between the visible sex appearance and the pre-natal brain development is just part of a much wider spectrum of unusual development – an interpretation acknowledged by Lady Butler-Sloss, (Court of Appeal, 2001): “There is, in informed medical circles, a growing momentum for the recognition of trans individuals for every purpose and in a manner similar to those who are intersexed”.
Factors which may be implicated in causing inconsistent fetal development may include genetic influences, environmental influences and/or medication to the mother during pregnancy. Rarely, unusual chromosomes configurations, e.g. XXY, XYY, XXYYY etc. or even a mosaic of more than one chromosomal pattern within different tissues in one individual, may also be associated with atypical development of gender identity and sex characteristics.
Some brain processes have been shown to be dissimilar in men and women in the population generally; hearing, for instance is ‘hard-wired’ differently. A recent study on the hearing of trans women demonstrated that it resembles the non-trans female pattern rather than the male pattern (Govier et al. 2009).
Previous research has established that small areas in the hypothalamic region of the brain are anatomically differentiated into male and female, in the general population. More recent research published in 1995, 2000 and 2008 undertaken by J-N Zhou et. al.; Frank Kruijver et. al. and Garci-Falgueras and Swaab respectively, demonstrated that in three small, but statistically robust, post-mortem studies of individuals experiencing gender dysphoria, two sex dimorphic areas – the central subdivision of the bed nucleus of the stria terminalis (BSTc) and the uncinate nucleus – are differentiated in opposition to the chromosomal, genital and gonadal sex characteristics.
This was found not to have been caused by cross-sex hormone administration nor by sex hormone variations in adulthood. Scans of white matter in the brains of untreated trans men and trans women show them to be masculinised and feminised respectively (Rametti et al, 2011). The gene coding for the androgen receptor which governs the body’s response to testosterone, is characterised by repeat polymorphisms in trans women, indication an atypical response to this hormone (Henningsson, 2005; Hare et al, 2008).
Monozygotic (identical) twins show a markedly raised incidence of concordance for transition compared with their dizygotic (fraternal) twin counterparts. These, and other findings, support the view that biological factors: genetic, hormonal, and chromosomal, may all have a part to play in strongly predisposing the formation of a gender identity that is at odds with the sex assigned at birth.
Where this predisposition exists, psycho-social factors may subsequently modify the outcome. However, there is no evidence that socialisation in contradiction to the phenotype causes gender dysphoria, nor that socialisation which is consistent with the phenotype can prevent it. Many trans men and trans women struggle to conform to stereotypical gender role behaviour from early childhood, through adolescence and into adulthood.
This may create intolerable stress which, in some individuals, can only be resolved by undergoing transition from the gender role imposed since birth, to the role consistent with the gender identity. This process does not change the underlying gender identity, but confirms it by aligning the phenotype with it, thus ending the mismatch. Trans people often delay transition to live in the opposite role, until they are adults, but a growing number do so during childhood or adolescence.
In conclusion, although the processes of sex differentiation of the brain are not yet fully understood, the evidence suggests that this is not a mental illness but rather a neuro-developmental condition. It is inevitable that trans people will not all be binary; many will be non-binary as there are many gender interpretations between ‘man’ or ‘woman.
Therefore treatment for these individuals needs to be tailored their own particular needs; it often includes hormone therapy and sometimes surgery, to achieve a closer alignment of the phenotype with the gender identity. Trans people usually benefit from psychological support for themselves and their families and significant others.
The World Health Organisation was advised, in 2013, to “abandon the psychopathological model, in favour of one that reflects current scientific evidence and best practice”. The World Professional Association for Transgender Health states that “the expression of gender characteristics, including identities, that are not stereotypically associated with one’s assigned sex at birth is a common and culturally diverse human phenomenon that should not be regarded as inherently pathological or negative.”