Researchers claim a newly developed test can predict a man’s sexual orientation with up to 70% accuracy.
The findings were presented at the American Society of Human Genetics 2015 Annual Meeting in Baltimore, MD, reports Medical News Today.
According to the researchers, the test can predict whether a man is heterosexual or homosexual. The test involves the use of an algorithm that can identify patterns of DNA methylation that may be related to sexual orientation.
DNA methylation is a molecular modification in DNA that controls gene expression. These modifications are triggered by environmental factors, such as diet, exercise, stress, and exposure to chemicals.
This is the ‘first example of a predictive model for sexual orientation based on molecular markers,” said study author Dr. Tuck C. Ngun of the University of California, Los Angeles.
To our knowledge, this is the first example of a predictive model for sexual orientation based on molecular markers.
Previous studies indicate that a person’s sexual orientation may be determined by the activity of specific genes, and this latest study builds on these findings.
Ngun and his colleagues conducted their research with 50 pairs of identical male twin participants, reports Science Alert. Thirty-seven of the pairs of brothers included one heterosexual and one homosexual brother, while a control group consisted of 10 pairs of twins with both homosexual brothers.
Saliva samples were taken from each of the participants to study any differences between the heterosexual and the homosexual twins that could show an environmental reason behind their sexual orientation. Epigenetic markers – molecules that affect how cells interpret DNA coding – could be a potential indicator of the theory, given that the twins’ genetic sequences would otherwise be identical.
The researchers developed a machine-learning algorithm called FuzzyForest to help sort through the data. FuzzyForest identified nine small regions across the twins’ genomes, which could be used to predict the participant’s sexual orientation.
While previous studies identified broad regions of chromosomes involved in sexual orientation, this new research was able to help the researchers “define these areas down to the base pair level,” said Ngun.
Previous studies had identified broader regions of chromosomes that were involved in sexual orientation, but we were able to define these areas down to the base pair level with our approach.
Other experts in the field claim that much more research will need to be conducted before Ngun and his team’s claims can be backed up.
In an unrelated study involving twins, researchers found that beauty really is in the eye of the beholder, or rather, based on personal experiences.