The biology of sexual orientation has been one of the most vexing — and politically charged — questions in human genetics. For the first time, researchers have found associations between homosexuality and markers attached to DNA that can be influenced by environmental factors.Wow, 67% of the time -- I bet I could do better than than just by peeking in their closets. Anyone want to lay odds on whether this finding will hold up over time, or fade away like all other claims about gay genetics have?
Twin studies and family trees provide strong evidence that sexual orientation is at least partly genetic. When one identical twin is gay, there is about a 20% chance that the other will be as well. But because this rate is not 100%, it is thought that environmental factors play a role as well. . . .
To search for factors that could mediate a link between environment and genes, geneticist Eric Vilain at the University of California, Los Angeles (UCLA), and his colleagues looked at epigenetic markers — chemical changes to DNA that affect how genes are expressed, but not the information they contain. These 'epi-marks' can be inherited, but can also be altered by environmental factors such as smoking, and are not always shared by identical twins
The researchers collected DNA samples in saliva from 37 pairs of identical twins in which only one twin was gay, and 10 pairs in which both were gay. By scanning the twins’ epigenomes, the researchers found five epi-marks that were more common among the gay men than in their genetically identical straight brothers. An algorithm they developed based on the five epi-marks could correctly predict the sexual orientation of men in the study 67% of the time.
This is not science -- this is the desperate search for any correlation that can survive basic statistical tests, so somebody can get a publication and keep his job.
Grrr. Grumble. Grrr.