Human family and twin studies have established considerable heritable components in personality traits as assessed by self‐report questionnaires. Recently, an association between a functional polymorphism in the upstream regulatory region of the serotonin transporter gene and neuroticism‐related personality traits was reported. Two different serotonin transporter polymorphisms including the previously associated variant were genotyped in two samples of healthy Swedish subjects (n = 127 and n = 178, respectively) assessed with the Karolinska Scales of Personality (KSP) inventory. No statistically significant association between serotonin transporter polymorphisms and any of the eight neuroticism‐related KSP scales was found. Thus, the previously reported association between serotonin transporter alleles and neuroticism‐related personality traits could not be replicated in the present study. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:430–436, 1999. © 1999 Wiley‐Liss, Inc.