A retrospective examination of antisocial and risk-taking behaviours

SNP rs10420324 in the AMPA receptor auxiliary subunit TARP γ-8 regulates the susceptibility to antisocial personality disorder

In the brain, AMPA receptors mediate fast excitatory neurotransmission, the dysfunction of which leads to neuropsychiatric disorders. Synaptic function of AMPA receptors is tightly controlled by a protein group called transmembrane AMPAR regulatory proteins (TARPs). TARP γ-8 (also known as CACNG8) preferentially expresses in the hippocampus, cortex and subcortical regions that are critical for emotion generation indicating its association with psychiatric disorders. Here, we identified rs10420324 (T/G), a SNP located in the human CACNG8 gene, regulated reporter gene expression in vitro and TARP γ-8 expression in the human brain. A guanine at the locus (rs10420324G) suppressed transcription likely through modulation of a local G-quadruplex DNA structure. Consistent with these observations, the frequency of rs10420324G was higher in patients with anti-social personality disorder (ASPD) than in controls, indicating that rs10420324G in CACNG8 is more voluntary for ASPD. We then characterized the behavior of TARP γ-8 knockout and heterozygous mice and found that consistent with ASPD patients who often exhibit impulsivity, aggression, risk taking, irresponsibility and callousness, a decreased γ-8 expression in mice displayed similar behaviors. Furthermore, we found that a decrease in TARP γ-8 expression impaired synaptic AMPAR functions in layer 2-3 pyramidal neurons of the prefrontal cortex, a brain region that inhibition leads to aggression, thus explaining, at least partially, the neuronal basis for the behavioral abnormality. Taken together, our study indicates that TARP γ-8 expression level is associated with ASPD, and that the TARP γ-8 knockout mouse is a valuable animal model for studying this psychiatric disease.

Measuring Engagement in Antisocial Behavior During Late Adolescence and Early Adulthood for Typically Developing Youth

Research examining the nature and extent of participation in antisocial behavior (ASB) in typically developing individuals during late adolescence and early adulthood remains rare. A self-report instrument for measuring participation in ASB was developed and administered to an Australian sample of 404 youth (64.9% females) aged 17 to 22-years using item-response theory methods. All participants reported involvement in multiple forms of ASB, although this involvement was skewed toward less serious behaviors, suggesting that engagement in these behaviors were common for typically developing youth. Unlike previous research, few sex differences were detected, with females' self-reported involvement in ASB similar to that of males. A need for ongoing longitudinal research in typically developing samples was highlighted, particularly on the transition to adulthood.