The homosexuality of men can be found everywhere. Some countries legalize same-sex marriage, while others prohibit them. Scientists have tried to understand the causes of homosexuality and to unravel the nature of the phenomenon.
Until recently accurate information about the causes of homosexuality men, there was no information of a scientific nature. It took a large-scale study of people with non-traditional orientation.
All scientists investigated 409 pairs of brothers gay. The volunteers were taken samples of blood and saliva.
It turned out that the tendency to homosexuality meet two genes. The first gene is located in the X chromosome, the second in the eighth chromosome.