How Can We Determine the Cause of Human Sexual Orientation?

The main purpose of this paper is to determine what is the dominate cause of sexual orientation. The experts have two main positions for this case: biological and environmental. These points of view sometimes contradict one another, sometimes they are intersected.

The environmental position based mostly on the Freud’s theory, looking at the childhood as the beginning of the personality formation and in the course of this, analyzing further develop of the individual in the society and family. The biological position is more scientific and reasonable, studying biochemical processes and specialties of the brain anatomy. The psychological causes have their arguments, based on the behavioral similarity aspect, when homosexually oriented boys choose female companies, and female jobs in future and inversely.  

The biological position proposes the theory of “gene code” and heredity, based on the brain anatomy and DNA differences. It shows the disposition and certitude of the sexual orientation. The twin studies show dual arguments. Monozygotic twins show 100% concordance of their sexual orientation and only 12% dizygotic twins show the same. Anyway it is an argument in the lineal theory favor. Besides, a recent study of Australian twins indicates that the tendency to enjoy activities conforming to traditional sex roles is biologically heritable (Bailey, Dunne, & Martin, 2000).

Without limiting the preceding, there is bisexualism, this orientation seems to combine these two theories, but anyway it is closer to the environmental position and still the most contradictory case.

Taking into account all abovementioned, we can not give a decisive answer to the main question about human sexual orientation. It is easy to believe in Xq28 “gay gene” and special anatomic features of the brain, on the other hand we have more complex environmental causes, with personality formation from childhood and further social influence in adulthood. The case is that they are both true, but the first is biological heredity that under a certain environmental influence determine human sexual orientation.