There is evidence to suggest that genes may influence criminal behaviours Essays

Submitted By Hannah-Summers
Words: 306
Pages: 2

There is evidence to suggest that genes may influence criminal behaviours, highlighting those individuals biology may increase the likelihood of them turning to crime. The role of serotonin is an important factor which regulates behaviour such as impulsive aggression. This neurotransmitter works in the brain to inhibit the firing of Amygdala, a structure in the brain which controls emotional responses. Therefore individuals with lower levels of serotonin means there is less inhibition in the Amygdala in an everyday circumstance however when a threatening event occurs the Amygdala will become overly active and because of this create a persons to act on their impulses such as aggression which in turn can lead to an act in violent crime.

The link between criminal behaviour and genetics can be shown in research from tin studies in which Monozygotic (identical) twins and dizygotic (non-identical) twin pairs are compared. Christiansen (1977) studied the data on 3,586 twin pairs and found concordance rates of 52% in MZs and 22% in DZs. This highlights that there is a genetic contribution to crime as the rates for MZs are as expected more similar than DZ twins on this criminal behaviour ‘trait’.

In addition to this another study is Brunner 1993 in which his findings show problems with monoamine metabolism which is associated with a deficit of (lack of) the enzyme monoamine oxidise A (MAOA). Highlighting a point mutation in the genetic mutations in the genes responsible for the…