Association between affective temperaments and brain-derived neurotrophic factor, glycogen synthase kinase 3ß and Wnt signaling pathway gene polymorphisms in healthy subjects.

ABSTRACT

BACKGROUND: There is increased attention towards elucidating genetic factors that underlie both psychiatric diseases as well as healthy psychological phenomena. Recent evidence suggests that temperamental traits, including affective temperaments, are heritable and associated with genetic polymorphisms. Genetic research examining affective temperaments using the Temperament Evaluation of the Memphis, Pisa, Paris, and San Diego Autoquestionnaire (TEMPS-A) may therefore elucidate the concept of a spectrum of mood disorders and the genetic relationship between affective temperaments and mood disorders. The purpose of this study was to examine the association between brain-derived neurotrophic factor (BDNF), glycogen synthase kinase 3ß(GSK3ß) and Wnt signaling pathway (Wnt) gene polymorphisms and affective temperaments in non-clinical Japanese subjects, as measured by TEMPS-A. METHODS: 44 healthy Japanese subjects were recruited through our university hospital and completed the TEMPS-A. We genotyped three SNPs (single nucleotide polymorphisms) from the BDNF, GSK3ßand Wnt genes in order to test the relationship between these gene variants and five affective temperaments measured by the TEMPS-A. RESULTS: No significant difference in the frequency of alleles between affective temperaments (depressive, cyclothymic, hyperthymic, irritable and anxious temperament) and non affective temperaments was shown. One-way analysis of variance (ANOVA) revealed no significant differences among 5 groups (depressive, cyclothymic, hyperthymic, irritable and anxious temperament) in healthy subjects for all the scores of affective temperaments by TEMPS-A. LIMITATIONS: The number of subjects was relatively small. CONCLUSIONS: The variant of BDNF, GSK3ß and Wnt gene polymorphism might not be related to the five temperaments of TEMPS-A and TEMPS-A score in healthy Japanese subjects. The present results suggest that BDNF, GSK3ßand Wnt genes, might not have a major role in the development of personality traits. Further studies with larger sample size are warranted to evaluate the association of affective temperament and gene polymorphisms.