NO ASSOCIATION BETWEEN BIPOLAR DISORDER AND ALLELES AT A FUNCTIONAL POLYMORPHISM IN THE COMT GENE - BIOMED EUROPEAN BIPOLAR COLLABORATIVE GROUP

Background There is compelling evidence For the existence of susceptib ility genes for bipolar disorder. Association studies using functional DNA variations are an important approach for identifying these genes. The enzyme catechol-O-methyltransferase (COMT) plays a key role in th e degradation of catecholamine neurotransmitters and is a candidate Fo r involvement in bipolar disorder. Recently a common functional geneti c polymorphism that underlies population variation in COMT activity ha s been elucidated and a simple assay developed. Method In a collaborat ion involving seven European centres, we have undertaken an associatio n study of this Functional polymorphism in 412 unrelated West European caucasian DSM - III - R bipolar patients and 368 ethnically matched c ontrols. Results We found no evidence of allelic or genotypic associat ion. Conclusions We can conclude that variation at this functional pol ymorphism does not make an important contribution to bipolar disorder in the Western European population. Future studies using this powerful experimental approach can be expected to contribute to identification of bipolar susceptibility genes.