The aim of this study is to investigate the influence of dopamine receptor D 2 ( DRD 2 ) , D 4 exon 3 ( DRD 4 ) , and gamma aminobutyric acid type A ( GABA ( A ) ) receptor alpha 1 subunit ( GABRA 1 ) gene variants on the efficacy of lithium prophylaxis in mood disorders . ^^^ Patients with mood disorders ( N = 125 : bipolar subtype , n = 100 ; major depressive disorder subtype , n = 25 ) were followed prospectively for an average of 53 months and were typed for DRD 2 ( Ser311 / Cys311 : n = 121 , VNTR : n = 63 ) , DRD 4 ( n = 125 ) and GABRA 1 ( n = 61 ) variants using polymerase chain reaction ( PCR ) techniques . ^^^ DRD 2 , DRD 4 and GABRA 1 variants were not associated with response to lithium . ^^^ DRD 2 , DRD 4 and GABRA 1 variants therefore do not appear to be associated with the outcome of lithium prophylaxis in mood disorders . . ^^^ |