I find lots of questions about this so called study.....
yes, I'm sure nature has its place...nuture has its place too...
learned behavior has its place as well....
personally, I find it hard how a human being born to procreate would have such an abnormality that it would not want to procreate....if this was the animal world, that abnormality would be selected out....
Replace the word "gay" with "red-haired" - do you understand, now?
Mere brothers (as opposed to identical twins) are not genetically identical.
Regards,