[NOTE: This was something Neorandomizer wrote a while back. I thought it was rather snazzy and deserved more attention than it would have gotten as a mere comment, so I (R3) am reprinting it here:]
The nature vs nurture debate has been around as long as old guys have had time to sit around and BS while the young go out to hunt the Mammoth. The debate picked up steam in the 19th century after Darwin's book on evolution and Doctors started to study human behavior from a scientific angle.
None of this would be a problem except that in the early 20th century the idea of eugenics became a popular pseudoscience and people started to apply their ideas to social engineering.
Eugenics is the idea that humanity can be improved by selective breeding.
None of the eugenics policies ended well. The most infamous was the German 'final solution' that lead to the Holocaust and the deaths of millions of Jews, Gypsies, Slavs, homosexuals, Catholics. The list of the people that is long. The Nazi's believed the elimination of would improve mankind.
The Nazis started slow at first: They passed laws that allowed court-ordered sterilization of defectives. They started with people that had developmental impairments and worked their way up to people that had diabetes, color blindness and other physical or mental disabilities. The really scary thing about all this was Nazi Germany based their laws on existing ones in the USA.
From the early 20th century into the 1960's many states had on the books laws that allowed someone to be declared an undesirable in court, and they could be ordered to be sterilized. In the 1930's planed parenthood was started by a woman that believed that the poor and minorities should be able to get abortions to reduce their populations; thus reducing the number of unproductive people. The Nazis, of course, took this idea to its logical conclusion and started to euthanize people. First people in mental institutions, and then they worked over to people that had polio and other incurable disabilities, all in the name of improving mankind.
Now all this would be just a scary part of history except the work that Dr. Marc Hauser did on morality ( http://www.republibot.com/content/science-fraud-primate-morality-reporte... )is not isolated about a decade back a scientist tried to prove that criminal behavior was genetic and children should be screened for this gene. His research turned out to be bogus.
Some years back a group of psychologists tried to have being conservative listed as a mental illness. They wrote articles on the subject and had a few followers until it was written about in the general media. They then tried the same genetic angle on being conservative. Of course these people were liberals, which, in their minds is the only 'healthy' way to think.
Research like Dr. Marc Hauser's has always been abused by people to justify suppressing unliked groups. It is always a good idea to keep an eye on this type of thing and the uses people wish to put it to.