Debate continues on whether or not male homosexuality (MH) is a result of biological or cultural factors. The debate persists despite the fact that these two sides have different abilities to create a scientific environment to support their cause. Biological theorists produced evidence, however, that these are not always robust. On the other hand, social theorists, without direct evidence confirming their positions, criticize, with good argument, methods and results of the other side.

Is there anything more controversial than homosexuality and its origin? Despite the evidence that bisexual or homosexual behaviour is largely practiced in nature, in close to 1,500 species no less, ranging from primates to gut worms [4], the majority of religious authorities, as well as some political institutions, consider sex with people of the same gender unnatural. Confusion between the level of biological evidence with the level of moral and metaphysic aspects has been and is, unfortunately, frequent. However, we can immediately answer the question in the title: yes, definitively, homosexuality is natural. Would this suggest that biology plays a major role in homosexuality? Probably, but not necessarily. While some people believe that sexual orientation is innate and fixed, for others, sexual orientation may develop across a person's lifetime. The words of John Bancroft, which conclude this Controversy, clarify several aspects of these opposite interpretations 5.

Controversy is limited to male homosexuality (MH) for three reasons: (i) homosexuality in males (HM) is more common than homosexual females; (ii) MH is much more scientifically studied than female homosexuality; and (iii) moral and religious concerns seem much more concentrated on HM than on lesbian behaviour. An impressive amount of empirical data suggests that biology is an important regulator of both heterosexual and homosexual behaviours. Evidence has been produced showing the importance of genetic, autoimmune, and neurohormonal factors in the development of sexual orientation. Criticizing methods and findings produced in the field of biology of sexual orientation 6.

Mustanski et al. admit that genetic research using family and twin methodologies has produced consistent evidence that genes influence sexual orientation, but molecular research has not yet produced compelling evidence for specific genes 7. Although it has been well established that older brothers increase the odds of homosexuality in men, the route by which this occurs has not been fully resolved. Even the robust and elegant evidence solving the Darwinian paradox (how an antireproductive gene may survive?) produced by Camperio-Ciani need to be confirmed in larger samples. This author discusses here the fertility advantages of carrying the "gene" of HM, using arguments similar to that known for the thalassemia trait, which may confer a degree of protection against malaria, prevalent in the regions where the trait is common, thus conferring a selective survival advantage on carriers and perpetuating the mutation

Inclusion Criteria:

• Age ≥ 18 years
• Male will be included

Exclusion Criteria:

• Patients taking testosterone or its derivative.
• Patients taking anabolic steroids.
• Multi-sexual behaviours.
• HIV patients.
• not having and addictive disorder

All individuals with homosexuality from these different locations, Egypt, England, China, and Mexico.