Remember Michelle Bachmann and her ditzy husband, Marcus?  With their fakokta programs to “fix” gay kids.  Like their “conversion therapy” was any more sound than TheDonald’s idea to stop hurricanes with nuclear weapons.

(Geez.  How do such geniuses rise up the GOP ranks?)

Not surprisingly, the science is coming in- hot and heavy.  (And, yes, I know the GOP only believes in their WrongWing concepts of religion- and never in science.  Like Diane Douglas, Superintendent of Public Education in Arizona [I kid you not] who declared that evolution cannot be taught in schools. Thankfully, Katherine [Kathy] Redden Hoffman (the daughter of one of my very special friends) squeaked by and overturned [after being declared the loser] this ‘educator’, reversing the decision.)

But, let’s get back to science.

Dr. Ben Neale of the Broad Institute (and his team, A Ganna, R Maier, and R Wedow) all of Broad Institute of MIT and Harvard); KJH Verweij and A Abellaoui (Amsterdam University); MG Nivard (Vrije University); P Lichtenstein and N Langstrom (Karolinska Institute); AS Busch and JRB Perry  (University of Cambridge); S Guo, GW Beecham, and ER Martin (University of Miami), JF Sathirapongsasuti and A Auton (23andMe), S Lundström (Goteberg University); KM Harris (U North Carolina); AR Sanders (Chicago); and BP  Zeitsch (Queensland)) published their research results in Science recently.  It’s clear that there is NO single (or even one of two or three) marker that determines if one is gay.  However, there are a series of genetic markers the delineate those whose preference is for same-sex partners.  These genes work in concert with one another.

We already suspected that- since studies of twins had suggested a genetic component in sexual orientation.  (This study goes back some 20 years!)  The study of families (40 pairs of gay brothers) indicated that about 1/3 of sexual behavior variation was the result of genetics. Their link was on the X chromosome, region Xq28 (which was promptly termed the gay gene).  Note- the replication of this study has not always been perfect.

But, as I have already outlined, the UK program, BioBank, that performs full medical and genetic identification of some 500K folks is providing the “big data’ we need to identify diseases and propensities among us.

As is true for many of these researchers who access this vast database, not all the data in the BioBank was used.  In this case, Dr. Neale used the surveys of sexual behavior (408995 from Biobank, matched with some 68527 23andMe genetic identification customers, [Both BioBank and 23andMe asked if the subject had engaged in sexual intercourse with someone of the same gender.]   The subjects analyzed were only those of European ancestry.  It should be noted (a shortcoming not discussed in the publication) that choosing only those of European ancestry may have limited the ability of the study to discern more of or all the possible factors.

Of those who answered yes to the survey, there were five genetic markers in common.  At first, the researchers honed in on two genetic markers.  But, when they separated the results by gender, they found two genes were specific to men and one was present only in the women.  They also found two genes that were not gender specific. (The genes specific to men and women may mean there are also hormonal influences to sexual preference.  For example, one of the genes in males is also related to baldness. Interestingly, another gene is related to our sense of smell- an important factor in sexual behavior.) These markers did not indicate that 100% of sexual preference was genetic- but genetics prevailed in at least 8% and as high as 25% of the cases.  Moreover, the marker genes were not predictors- just that they prevailed among subjects involved in same-sex behaviors.

(In the chicken and egg scenario, those subjects also were more likely to use marijuana and at higher risk of manifesting depression.  [Please note that LGBTQ folks manifest depression and other mental maladies as a result of the societal pressures and biases to which they are subjected.])

So, unless more matches are found, it is possible that 75% of the gender specific sexual drive is beyond genetics.  But, it does challenge the validity of the “Kinsey Scale”- the theory that there is a single continuum between hetero- and homo- sexuality- or that the more one is attracted to one gender, the less likely the person would be attracted to the other gender.

But, let’s not forget that despite the ‘universe’ of 466,522 participants, only 26,287 engaged in same-sex behaviors.  That is not enough to fully identify the series of genes or pathways that may prevail among such subjects.

Basically, the study demonstrated that sexual orientation is far more complex than an association with a gene (or even a few genes); there are multiple factors. In other words, it is a natural part of the human experience.

 

As a follow-through, a new website has been developed,  Genetics of Sexual Behavior.  The goal of the website is to communicate and explain the findings of this study.  (This helped them adjust their publication in Science to focus on behavior, rather than sexual identity or orientation.