IQ is inherited.Environment plays a part(in intelligence)as well."It's not scientific".Do you mean it can't be measured?Wrong again.No IQ test is perfect,but testing can provide meaningful measurement.Your reference to homosexuality,could it be an "inherited connection"?I belive it is possible.What's wrong with that?Do you believe it's possible?
Intelligence cannot be measured scientifically. Test until your hearts content, but do not be a biological determinist and fall for the fallacy of believing that you can quantify or assign a single entity to the abstraction of intelligence. Once you do this... then you naturally fall into the second fallacy of ranking.
American Psychologists of the past took these hard "objective" number values and have used them to form ever more complex arguements of worthiness to rank race, class, sex, or to even find those that them deem inferior or even deserve their status.
I believe that intelligence is acquired. Whatever one generation learns it can pass to the next by teaching, writings, traditions, rituals, etc.
Homosexuality could be genetic...if so...it could be cured. Would the homosexuals want that...or are they content with their behavior even though they are not following their biological form and function?