Let me reiterate this point, as it is crucial: a gene codes for a protein, or it affects the production of proteins. There is nothing else we currently know of that a gene does.
Why, then, is there such talk of a genetic basis of behaviour? Because if behaviour is rooted in genetics, either we are saying that a protein produces behaviour (which we shall see shortly is absurd), or we are claiming that behaviour emerges somehow from genes in a manner we don’t understand and cannot currently prove – at which point the honest scientific position is to admit that we do not know how behaviour is inherited.
Is het waar dat er een onbekend (en momenteel onbewijsbaar) proces betrokken is bij de interactie tussen genen en gedrag?
Zijn er ideeën wat voor proces dit kan zijn?
The bottom line is that while virtually all behaviour can be influenced by genes, there is no evidence that behaviour is determined by genes. There is no gay gene, no gene for intelligence, no gene for violence, no gene for reliability, no gene for amiability… there is no gene for any behaviour, neither does it seem likely that any such gene will be found. Errors in genes can cause specific medical conditions (which have behaviours associated with them), as with Down’s syndrome for instance, but that is as far as the body of research currently goes.
In 1994, the journal Science published an article by Charles Mann entitles Genes and Behaviour which contained this apposite quote:
Time and time again, scientists have claimed that particular genes or chromosomal regions are associated with behavioral traits, only to withdraw their findings when they were not replicated. "Unfortunately," says Yale's [Dr. Joel] Gelernter, "it's hard to come up with many findings linking specific genes to complex human behaviors that have been replicated. "...All were announced with great fanfare; all were greeted unskeptically in the popular press; all are now in disrepute.
Klopt het dat bevindingen die een verband tussen gedrag aan genen leggen, bijna nooit gerepliceerd worden? En zoja, waarom worden deze bevindingen dan zo gehyped en snel geloofd?