Could the ‘gay gene’ be right in front of us?
I鈥檝e thought of a new hypothesis about the genetic basis for sexual attraction in the human population (both male and female, heterosexual and homosexual).
Given the importance in evolution that attraction to the opposite sex has for the continuation of the species, this property could not be left to chance and would have to be encoded in our genes.
It seems to me that scientists (especially those attempting to find a 鈥済ay鈥� gene) should be trying to identify the gene and the product of that gene causing sexual attraction to the opposite sex.
(I use the word 鈥済ene鈥� in the singular here for ease of expression although, in all probability, there will be a set of genes, and ultimately there will be many interactions when one comes to the question of sexual behaviour, some of which will be genetic and others will not be of a genetic nature.)
Early studies on the family tree of homosexual males pointed to the fact that the genetic trait of homosexuality carried by these individuals was inherited from their heterosexual mothers and later researchers concentrated their studies on the X chromosome.
If the gene coding for 鈥渟exual attraction鈥� is carried on the X chromosome in the gay male, is it not reasonable to conclude that the gene for determining sexual attraction in the remainder of the human population is also carried on the X chromosome?
This is my starting hypothesis: The gay male has the same genetic coding as the heterosexual female. There is no mutation and no 鈥済ay gene鈥� 鈥� just an inheritance by the male of a gene normally found in the female.
There is no requirement for scientists to find an evolutionary advantage in the individual carrying a gay gene. Any supposed advantage will have been carried by his mother, the heterosexual female, in being (genetically) more licentious. How could this come about?
I postulate that there are three variants (with respect to coding for sexual orientation) of the X chromosome in the human population responsible for the genetic basis of sexual attraction.
As stated above and elsewhere, actual sexual behaviour of an individual will be the result of many factors, both genetic and non-genetic such as social, peer and religious pressures and could vary during the lifetime of that individual.
By NORMAN COLES
INFO: Norman Coles holds a Master of Science from Sydney University and a PhD from McGill University in Montreal, Canada, both majoring in biochemistry.
