Homosexuality: Nature vs. Nurture

The debate between nature and nurture has come to the forefront of the public’s mind especially in regard to homosexuality. Is it something you’re born with, or is it a result of your upbringing? Some scientists believe that they may be close to finding a “gay gene.”

In a study published in October, scientist Erik Jorgensen and a team of researchers changed the sexual behavior of nematode worms. Male nematodes use sensory neurons to find females, since they are blind. On the other hand, most nematodes are hermaphrodites, producing sperm so they can fertilize their own eggs without finding a male. Hermaphrodites are essentially females because they do not seek other hermaphrodites to mate with. In this study, the OSM-9 gene was determined to be related to sexual attraction through pheromone sensory neurons. It was determined that males without sex specific neurons like the ones OSM-9 codes for are still attracted to pheromones, and hermaphrodites whose core neurons were masculinized were also attracted to the same pheromones.

This study has reminded many of another study published in the summer of 1993 by Dan Hamer about a possible homosexuality gene in humans. There have been studies on families with two or more gay brothers, and it was found that they share about 60% of genetic patterns, which is more than the expected 50% that they would share by sheer statistical probability. Researchers believe to have isolated areas on chromosome 7 and 8 that may be associated with homosexuality, and another area on chromosome 10 that only has an effect if it is inherited from the mother. It is uncertain what these areas of DNA might code for, whether it is transcription factors, promoter regions, or a coding sequence. In order for these conclusions to be validated, the study must be duplicated with similar results.

There was also a study conducted in Canada by Dr. Bogaert to determine if birth order had an effect on the probability of homosexuality in males. Over 400 gay and straight men were surveyed, and Bogaert and his team of researchers found that younger sons have a higher likelihood to be homosexuals regardless of time spent with their biological brothers. Also, step-brothers had no effect of the sexual orientation of the men surveyed. Therefore, Bogaet concludes that there must be some determining factor in the womb that predisposes children to be either gay or straight.

While evidence is pointing to DNA as the cause of homosexuality, scientists are not saying that this definitely means it is genetically inherited, but some of the media has been portraying it that way. The interactions between DNA and the environment are far more complex than the public is led to believe, and homosexuality, unlike some physical traits, is not directly inherited, but it is a balance between genetic and environmental factors. There is more than meets the eye to this issue, which brings us to how a conclusion in this debate may affect our society.

Gay marriage is already a major political issue, with all of the presidential frontrunners opposing gay marriage; however, they all also oppose an amendment banning it. Clinton and Obama both support civil unions, and McCain supports legal benefits for same-sex couples. If homosexuality is determined to be entirely genetic, will it alter the mainstream opinion or marriage rights in any way? The repercussions may also affect all aspects of our society, including religious views, genetic engineering of children, and social acceptability.

By Nicole Eckart