Prevalence of Gender Identity Disorder (GID)
We discussed previously that
GID is a
disorder in which a person persistently feels extremely uncomfortable about his
or her assigned sex and strongly wishes to be a member of the opposite sex.
These disorder are rare in
comparison to most of the other mental disorders. Male-to-female transexuals
are more common than female-to-male transexuals. Men with GID outnumber women
by around 2 to 1. Some studies estimate the prevalence to be approximately
1:12,000 in males and 1:30,000 in females (Olsson & Moller, 2003. Overall,
the prevalence of GID ranges from 0.003% to 3% in boys and 0.001% to 1.5% in
girls (Bartlett, et al., 2000).
Gender Identity Disorder Etiology
Very little is known about their etiology of
GID. Cause is largely unknown, however, various theories have been proposed to
explain this disorder, but research to test the ideas has been limited and
generally weak. For instance, theorist have suggested that GID is the result of
an absent father (Stoller, 1979), a mother being enmeshed with her son ( Loeb
and Shane, 1982), the parents wishing they had had a child of the opposite sex
(Green, 1974), or transsexuals had more feminised 2D:4D ratios finger
length(Schneider et al. 2006). After reading several research regarding the
etiology of GID, I found that the biological factors play a crucial role in
this disorder. Here are some research that support the biological proposal:
1)Hormonal influences
There are some research pointed
out that gender identity is strongly influenced by sex hormones , especially
during the prenatal period (Diamond, 2009). Early reports suggested that plasma
testosterone was lower in MtF transsexuals when compared to heterosexual men
(Starká et al., 1975) and higher in FtM transsexual when compared
to heterosexual women (Spiová and Starká, 1977). In addition, there is an interesting set of data
comes from studies of people with a condition called pseudohermaphroditism.
Individuals with this condition are genetically male, but they are unable to
produce hormone that is responsible for shaping the male genital in the fetus. Therefore,
the child is born with external genitalia that are ambiguous in appearance.
Many of these children are raised as girls by their families , when they reach
puberty, a sudden increase in testosterone leads to dramatic changes in the primary
sexual characteristic of the adolescent's such as clitoris become enlarged and
turns into penis, deeper voice, increasing muscle mass and etc. The child
quickly begins to consider himself to be a man. The speed and apparent ease that
these children adopt a masculine gender identity suggest that their brains had
been prenatally programmed for this alternative (Hines, 2004)
2) Brain correlational studies
One biological has received
considerable attention (Zhou et al., 1995). This research was to examine the
sex difference in the human brain and its relation to transsexuality. Dutch
investigators autopsied the brains of six people who had changed their sex from male to female (MtF). They found that the
transsexuals' bed nucleus of stria terminalis of the hypothalamus (BST) was
only half as large in these subjects as it was in a control group of normal men
(generally, woman's BST is much smaller than a man's). Scientist do not know
the function of BST in humans but they know that it helps control sexual
behaviour in male rats. This research proposed that men who develop GID have a
key biological difference that leaves them very uncomfortable with their
assigned sex characteristics.
3) Bruce/Brenda and David Reimer (A case of a Boy being raised as a Girl)
In 1967, a Canadian couple
brought their two identical twin boy (8 months old) to the hospital for routine
circumcisions. A surgical mistake during one of the twin's circumcisions
resulted in the destruction of his penis. The couple met with Dr.John Money, a
well-known medical psychologist who believed that gender was learned and could
be changed through child rearing. After meeting with Dr.Money and discussing
their options, the couple decided to have their son, Bruce, undergo castration
and have surgery to transform his genitals into those of an anatomically
correct female. Bruce became Brenda and was raised as a girl. She was put on
hormone treatment beginning in adolescence to maintain her feminine appearance.
For many years, this Brenda/Bruce
case stood as "proof" that children were psychosexually
"neutral" at birth and that gender could be assigned , no matter what
the genetic or biology indicated. However, no one paid much attention to the
fact that Brenda was struggling against her girlhood and gender identity from the beginning. Once
Brenda reached puberty, despite her hormone treatments, her misery increased.
She became depressed and suicidal. She never felt that she was a girl, and she
was relentlessly teased by peers. Her parents finally told her the truth, and
at 15 years old, she stopped hormonal treatment and changed her name to David.
Soon afterward, David went
public with this medical story in hopes of discouraging similar sex assignment
(especially nonconsenting minors) and published his real-life story in a book
called As nature Made Him: The Boy Who
Raised as a Girl. This book, in conjunction with interview with David,
influenced medical understanding about the biology of gender.
Although David eventually
married and adopted children, his struggles with depression continued. In 2004,
at age 38, David committed suicide.
These are the links of YouTube
video where you could watch the interview with David Reimer (Part 1 to Part 5)
I always feel downhearted
whenever I read through David's story. His life became a tragedy because of our
poor medical understanding about the biology of gender and gender identity. From
his case, we might conclude that gender
is innate and cannot be overridden by nurture or social learning. Indeed,
more research should be done to find out the biology of gender as well as etiology of GID to prevent another tragedy from happening. Research could
also benefit psychology clinical practice in terms of the diagnostic assessment
and treatment plan.
References
Carroll JL. (2010). Sexuality Now: Embracing diversity (3rd ed).
Belmont: Wadsworth Cengage Learning.
Bartlett, N.H., Vasey, P.L.,
Bukowski, W. (2000). Is gender identity disorder in children a mental disorder.
Sex Roles, 43(11-12), 753-785.
Diamond, M. (2009). Clinical
implications of the organizational and activational effects of hormones. Hormones and Behavior, 55, 621-632
Green R (1974). Sexual Identity
Conflict in Children and Adults. New York: Basic Books.
Hines, M. (2004). Psychosexual
development in individuals who have female pseudohermaphroditism. Child and Adolescent Psychiatric Clinics of
North America, 13, 641-656
Loeb L and Shane M (1982). The
resolution of a transsexual wish in a five-year-old boy. Journal of the American Psychoanalytic Association 30: 419-434.
Olsson, S., & Moller, A. R.
(2003). On the incidence and sex ratio of transsexualism in Sweden, 1972-2002. Archives of sexual behaviour, 32,
381-386.
Schneider HJ, Pickel J, & Stalla
GK (2006). Typical female 2nd-4th finger length (2D:4D) ratios in
male-to-female transsexuals - possible implications for prenatal androgen
exposure. Psychoneuroendocrinology 31:
265-269.
Spiová L, Starká L (1977). Plasma testosterone values in transsexual women. Archieves of Sexual Behaviour 6:477-481.
Starká L, Spiová L, & Hynie J (1975). Plasma testosterone in male
transsexuals and homosexuals. Journal of
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Stoller RJ (1979). Fathers of
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Zhou JH, Hofman MA, Gooren LJ,
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