Negative association between T102C polymorphism at the 5-HT2A receptor gene and bipolar affective disorders in Singaporean Chinese

Background: Serotonergic system abnormalities have been implicated in the pathogenesis of bipolar affective disorders. The 5-hydroxytryptamine type 2A (5HTR2A) receptor gene located on chromosome 13 (13q14–21) can be considered as a candidate gene for bipolar affective disorder (BPAD). Methods: Seventy-two patients with BPAD and 74 normal population controls were genotyped with restriction fragment length polymorphism (RFLP) in the 5HTR2A receptor gene. Results: We report a negative association between 5HTR2A receptor gene and BPAD. The association was examined using a case-control design. Allele and genotype frequencies as well as homozygote–heterozygote distribution at the 5HTR2A receptor gene polymorphism were compared between the two groups. There were no significant differences in the allelic or genotype frequencies and the homozygote–heterozygote distributions. Limitations: Patients were recruited from one hospital in Singapore. The case-control study design needs replication. Conclusion: Our finding indicates that the 5HTR2A receptor gene polymorphism is not a major factor in the genetic susceptibility to BPAD in Singaporean Chinese.