There are reasons why genes have been the cause of criminal behavior. Recently, many studies have been carried out: “Recent studies in behavioral genetics indicate that some violent criminals are genetically predisposed to violent behavior. One study found that a mutation in the structural gene for monoamine oxidase A gives rise to an acute accumulation of neurotransmitters associated with the body's "fight or flight" responses to stressful situations (Evansburg 2001)" (Wilson) . The study showed that: “it focused on the question of whether genes are likely to cause a person to become a lifelong repeat offender, characterized by antisocial behavior during childhood that can then progress to violent or serious criminal acts later in life. » (Barnes). What these studies indicate is that criminologists are trying to determine whether genes contribute to people becoming criminals. Another study looked at twins and monitored their behavior in different situations. This study showed: “comparing monozygotic (MZ) or identical twins and their rates of criminal behavior with the ra...