UC Merced

This paper reviews the outcome of serotonin production in callous-unemotional (CU) traits, varied by the SLC6A4 gene’s 5-HTTLPR repeat polymorphisms, which includes the short-allele by 44bp deletion and long-allele by 44bp insertion. Specifically, this research looked into the long-allele possibly causing decreased serotonin production, resulting in CU-traits. Previous studies found psychopathic key characteristics to be environmentally and genetically influenced in unique ways, with CU-traits being genetically affected by 5-HTTLPR polymorphisms. This research was conducted by searching for articles with keywords on the Google Scholar search engine, such as “psychopathic risk factors” and “psychopathy in adolescents.” A focus of 5-HTTLPR polymorphisms was established by its observed repetitive mentions, followed by filtering out unrelated sources already collected, then synthesizing the remaining information deemed relevant to the respectively formed research question. The data search surrounded adolescents between 12-19 year-olds, but was supported by data of other age groups, also due to severely limited research on CU-adolescents. Results within these studies were typically derived from neuroimaging, PCR, twin studies, and checklists. Treatments for psychopathic adolescents are based on positive encouragement, a preventative technique stemming from the biological foundations of CU-specific psychopathy. It was concluded that serotonin production is not depleted, but has fast reuptake from the synaptic cleft by increased 5-HT transporter mRNA. This lowers serotonin usage availability, which has been tightly associated with CU traits from previous research. Further studies should focus more on trying to understand the mechanisms of the long-allele directly impacting increased 5-HT transporter mRNA concentrations.