This study may be (and likely is) “total crappola,” but the link you posted doesn’t prove a thing. All your link says is that, by 1997 (15 years ago), “[n]o researched ha[d] found provable biological or genetic differences between heterosexuals and homosexuals that weren’t caused by their behavior.” That does not prove that these researchers, in 2012, did not find such differences.
That was not my intent with posting the link. My intent was to provide an answer, based on scientific research, to the question ... 'What Causes Homosexuality?' Contrary to the failed, yet obsessive, quest for the 'holy grail' of a 'Gay' gene, researchers in the field have already identified the multiple environmental (family, homosexual/unusual sex experience in childhood, cultural indoctrination) [described at length on the link I posted] factors that have led to homosexuality.
The completely ridiculous, illogical and contradictory to the scientific data itself, conclusions of these researchers, in 2012, are themselves proof of it being crappola.