Theories on sexual orientation

Is there a ‘gay gene’?

The term 'gay gene' refers to the gene that is thought to determine one’s sexuality. Whether this gene actually exists is still subject to scientific debate.

Several studies have found there to be a genetic influence on the determining of one’s sexuality — whether it be the levels of one’s hormones or the size of certain parts of the brain (i.e. the corpus callosum or medulla oblongata). However, there is no conclusive proof that homosexuality is completely determined by genetic factors.

Eye colour, for example, is determined 100% by genetic factors, but height is only 90% determinable and is influenced by other factors such as nutrition. Because of this, height is said to be a ‘multifactorial’ trait. Studies of monozygotic (identical) twins revealed that if one brother is gay, there is a 52% chance that his twin is gay, suggesting a 70% attributable genetic factor (Bailey and Pillard, A Genetic Story of Male Sexual Orientation, 1990).

In the absence of conclusive proof as to whether homosexuality is completely biologically determined, the best answer is that the most current scientific studies suggest it to be a combination of environmental and biological factors. John Money, Emeritus Professor of Paediatrics at John Hopkins University, Maryland, USA, summarises the current scientific crux:
"Homosexuality is multi-varied. There is certainly a genetic component but there is not enough data to state that it is an exclusive influence. Hormones that affect the foetus play a part."
Could You Be Gay for a Day?
Daily Express, 7 July 1996 

Even though popular medical opinion is not certain of the exact role that genetic factors play in determining one’s sexual orientation, it is certain that homosexuality is not a disorder of any kind and should not be treated as such.

Homosexuality is not a mental illness

As early as the 1950s new medical research indicated that lesbians and gay men were not suffering from mental illness and could lead happy and productive lives. By the 1970s popular medical opinion reflected this research. Today there are few medical professionals that give the age-old "mental illness" diagnosis for gay and lesbian patients.

The Royal College of Nursing agrees, stating in its "Issues in Nursing Health Series" (10/97) that "there is no intrinsic relationship between sexual orientation and mental illness. Homosexuality is not a mental disorder and there is no difference overall in the adjustment of people with same-sex or opposite-sex orientations."

The American Psychiatric Association officially declassified homosexuality as a mental illness in 1974 but it wasn't until 1992 that the World Health Organisation followed suit.

Even though homosexuality is no longer classified as a mental illness, as the RCN states:

"There is a long legacy of an association between the two which continues to have an impact."

As a result of this homophobia, there are counsellors who still insist on "reparative therapy" to combat same-sex attractions. This type of therapy is destructive, reinforcing self-hatred and contributing to unhappiness.

To find out more about reparative therapy, visit our health microsite 

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