Molecular genetics of personality

Although initial reports of genetic contributions to personality dimensions were promising, continued empirical support remains controversial. The focus has largely revolved around polymorphisms of the serotonin transporter gene-linked polymorphic region and the D4 dopamine receptor subtype. Equivocal findings likely stem from numerous sources including ethnic diversity of subject samples, phenotypic characterization of personality traits, and insufficient sample sizes. Research has begun to shy away from single gene causation in support of more complex polygenic models of personality traits. This search has identified numerous other candidate genes including dopamine D2 and D3 receptor subtypes, serotonin receptors, and catecholaminergic enzymes, to name a few. This article endeavors to review and evaluate the most recent literature within the context of this burgeoning field. Some considerations for future research are presented in summary.