Since then, questions arose regarding the validity of those results. That study linked DNA markers on the X chromosome to male sexual orientation. Gay Gene DebateĪ heated debate over the existence of a 'gay gene' emerged from a 1993 report published in the journal Science by then-NIH researcher Dean Hamer, PhD. The findings show that identical stretches of DNA on three chromosomes were shared by about 60% of gay brothers in the study compared to the about 50% normally expected by chance. But this study examined genetic information on all chromosomes, including genes from the father. Genes on this chromosome are only passed to a son from his mother.
Those previous studies looked only at the genes located on the X chromosome. 'It builds on previous studies that have consistently found evidence of genetic influence on sexual orientation, but our study is the first to look at exactly where those genes are located,' says researcher Brian Mustanski, PhD, a psychologist at the University of Illinois at Chicago. The results suggest that several genetic regions may influence homosexuality. Researchers say it's the first time the entire human genetic makeup has been scanned in search of possible genetic determinants of male sexual orientation. 28, 2005 - The genes a man gets from his mother and father may play an important role in determining whether he is gay or not, according to a new study likely to reignite the 'gay gene' debate.
