Background. There is evidence for an association between two different polymorphisms of the
human serotonin transporter gene (5-HTT) and the personality trait of neuroticism and affective
Methods. We studied the association between neuroticism and polymorphisms in the 5HTT-linked
promoter region and in a variable number tandem repeat region (VNTR) of the 5-HTT gene in 204
people aged over 60 derived from a random sample of men and women in the general population.
Approximately half of the subjects were in the top 20% of neuroticism scorers and half in the
Results. There were no significant differences in allelic or genotypic frequencies between the high
and low neuroticism scorers. There was highly significant linkage disequilibrium between the two
5-HTT gene polymorphisms, and haplotype analysis showed no association between neuroticism
level and haplotype.
Conclusions. Reports of an association between two 5-HTT gene polymorphisms and the
personality trait of neuroticism are not supported by these results.