Babies less prone to feel fear are more likely to commit crimes.

Even at the tender age of 3, children who will go on to be convicted of a crime are less likely to learn to link fear with a certain noise than those who don't. This may mean that an insensitivity to fear could be a driving force behind criminal behaviour.

Adult criminals tend to be fearless, but whether this characteristic emerges before or after they commit a crime wasn't clear, says Adrian Raine, a psychologist at the University of Pennsylvania in Philadelphia.

Will people choosing genetic alleles for their genetically engineered children make them more or less predisposed to feel fear than the average human today? The answer will at least partially determine whether embryo selection for preferred genes will make future humans more or less criminal than they are today.

Raine does a lot of interesting work on innate causes of behavior. See my posts Brain Scans Show Abnormalities In Psychopaths and Habitual Liar Brains Look Different On Scans for more interesting brain research from Raine.