Is an individual’s sexual orientation determined even before they are born? That in any case is what is claimed by Professor Jacques Balthazart, of the GIGA-neurosciences centre, in making use of the copious scientific literature fed by experiments on animals and by human clinical medicine. Far from the clichés it serves as a vehicle for, homosexuality is said to be neither a ‘disease’ nor a deviancy, and nor can it be attributed to the family and socio-cultural context the individual has been brought up in. A bad day for homophobia!

Where are the roots of homosexuality to be found? Derived from Freudian and post-Freudian ideas, the most commonly accepted theory postulates that this sexual orientation is mainly, if not exclusively, pinned together in early childhood, in the learning acquisitions and interactions which take place during it, and in particular in the interactions between the young child and his/her parents. In this context, homosexuality is the result of a block in the development of the libido at an immature stage.

In his book Biologie de l'homosexualité – On naît homosexuel, on ne choisit pas de l'être (The Biology of Sexuality – We are born homosexual, we don’t choose to be (1), Professor Jacques Balthazart, the director of the Behavioural Neuroendocrinology Research Group in the GIGA-neurosciences centre at the University of Liège, contests this thesis, judging that not a single controlled quantitative study has corroborated it and that it scorns the today abundant data of scientific literature. In precise terms, what path is traced out by these biological data, stemming essentially from human clinical medicine and experiments on animals? The one which leads Jacques Balthazart to declare that homosexuality depends to a great extent on three types of prenatal influence: hormonal (mainly), genetic and maybe immunological. ‘Given the complexity of a human being, this does not rule out that there can exist homosexuals for whom this orientation constitutes a deliberate life choice, possibly influenced by earlier experiences,’ he states. ‘Nevertheless, a large proportion of homosexuals are born with this inclination.’

A sexual preference for individuals of the same sex, homosexuality must not be confused with homosexual activity. For animals as much for human beings – the case of prison environments is well known – practicing ‘intimate’ relations with an individual of the same sex is likely to occur in any situation where a partner of the opposite sex is not available. There more over exist numerous civilizations where – as in Papua New Guinea – homosexual relationships are the norm for adolescents. They can in particular be inscribed within a framework of initiation or have the goal of preserving the virginity of young girls. ‘In the countries concerned, the level of homosexuality at adult age is from 5 to 10%, the same as in any other population,’ comments Professor Balthazart. ‘I see in that an argument to refute the theories which attribute its origin to precocious learning acquisitions which fashion long term preferences.’