Abnormal neurology due to a pathogen such as a virus, bacteria, or fungal infection will account for at least some of lgbt disorders. https://evoandproud.blogspot.com/2009/02/origins-of-male-homosexuality-germ.html https://www.gwern.net/docs/genetics/selection/2000-cochran.pdf A genetic disease called non-classical congenital adrenal hyperplasia is associated with lesbianism in women.