Increasing evidence supports that 5HTTLPR polymorphism of the serotonin transporter gene(5HTTLPR) might associate to bipolar disorder and affective temperaments as measured by TEMPS-A. But the results are discrepant, furthermore, there are no data from Chinese population.

The present study was designed to investigate association between 5HTTLPR and bipolar disorder and affective temperaments of patients with bipolar disorder in the specific Chinese population and add new evidence to the field.

There hundred and five patients with bipolar disorder and 272 normal controls were included in the present case-control study⌧Temperament Evaluation of Memphis, Pisa, Paris and San Diego -autoquestionnaire version (TEMPS-A) in Chinese was used to assess affective temperament. Chi-square test, T test, Nonparametric test and ANOVA were employed to explore association between 5HTTLPR polymorphism and bipolar disorder and affective temperament of patients with bipolar disorder.

5-HTTLPR L/S polymorphism was associated with bipolar disorder in female (genotype χ²=6.769⌧P=0.034⌧allele χ²=6.028⌧P=0.014) and the S allele was associated with anxious temperament (t=8.248⌧P=0.005) in patients with bipolar disorder. The LA allele of 5-HTTLPR rs25531 A/G polymorphism was associated with hyperthymic temperament in patients with bipolar disorder (Z=−2.205⌧P=0.027).

5-HTTLPR might have an effect on the prevalence of bipolar disorder in female and regulate affective temperaments of patients with bipolar disorder in some degree in Chinese population.