What is the validity of Hamer's 'gay gene'? We can do no better than quote verbatim from Peter Little's book Genetic Destinies(1)
"So does this mean that scientists have discovered a "gay gene" as many newspaper reports suggested? Of course not: as is so often the case, the scientific truth is far less exciting than the headline suggests. I think it is worth simply listing what was actually found in the original study compared with what the headlines imply was found."
- There is a gene for homosexuality, found only in such men.
No. No gene has been discovered, just a region on the X chromosome region that should contain a gene (or genes) with a difference that contributes to this sexual preference.
- The gene difference makes a man homosexual.
No. It makes a small contribution to the reasons why some males are homosexual: background, upbringing, and environment all have even greater impact than the gene difference on the X chromosome.
- The gene contributes to the behaviour of all male homosexuals.
No. The homosexuals studied in this research all came from carefully selected individuals with a clear family history of homosexuality. The study suggests that the gene difference on the X chromosome contributes to a man becoming homosexual in these families, but this may not be the case in other families where differences in completely different genes might be responsible. Until we know what the gene is and how it is different we cannot study this question. Once (and if) we know this, we can then see if the same difference occurs in many additional homosexuals and knowing this would allow us to conclude, or not, if the gene difference contributes to the behaviour of all male homosexuals.
- Little, P., (2002) Genetic Destinies Oxford :Oxford University Press Bookshelf
- Roughgarden, J., (2004) Evolution's Rainbow: Diversity, Gender and Sexuality in Nature and People University of California Press. Bookshelf