Table 2.
Dopaminergic and noradrenergic gene polymorphisms in MDD.
| Reference | Candidate gene | Population/sample size | Main findings |
|---|---|---|---|
| (122) | Norepinephrine transporter (NET) | 34 brain tissue samples (19 healthy controls) | Reduced NET in the LC related to MDD. |
| (123) | NET | 179 (74 healthy controls) | No significant associations. |
| (124) | NET | 200 (100 healthy controls) | No significant associations. |
| (125) | NET | 248 (136 healthy controls) | Tendency for lower TT genotype frequency in MDD. |
| (126) | NET and 5-HTT | 96 depressed subjects | T-allele of NET T-182C polymorphism associated with better antidepressant response. |
| (127) | NET | 309 (164 healthy controls) | C/C genotype related to low MDD risk. |
| (128) | NET | 426 (210 healthy controls) | No significant difference. |
| (129) | NET | 776 (388 healthy controls) | Selected NET gene polymorphisms influence MDD risk from negative life events. |
| (130) | NET and 5- HTTLPR | 579 depressed subjects | Both NET and 5-HTTLPR related to MDD, while the interaction between them associated with depression and Hamilton Depression Rating Scale for Depression baseline scores. |
| (131) | NET, and 5-HTTLPR | 252 depressed subjects | No significant associations between selected polymorphisms and antidepressant response. |
| (132) | the norepinephrine transporter (SLC6A2), HTR1A, and COMT | 126 depressed subjects | No significant associations between SLC6A2 polymorphisms and antidepressant treatment response. |
| (133) | SLC6A2, TPH2 | 205 depressed subjects | SLC6A2 polymorphism related to MADRS-defined olanzapine+fluoxetine response in MDD. |
| (134) | SLC6A2 | 550 (201 with MDD and suicide attempts, 160 with MDD without suicide attempts, and 189 healthy controls) | SLC6A2 polymorphism related to suicide risk in MDD. |
| (135) | NET | 604 (302 healthy controls) | CC genotype of NET gene may reduce risk of depression. |
| (136) | SLC6A2 | 243 depressed subjects | Association between SLC6A2 gene variation and remission after venlafaxine treatment in MDD. |
| (137) | NET | 776 (388 healthy controls) | Significant association between T-182C polymorphism and MDD. |
| (138) | SLC6A4, NET, HTR1A, HTR2A, COMT, and brain-derived neurotrophic factor (BDNF) | 53 (27 healthy controls) | No difference in NET polymorphisms between MDD group and controls. |
| (139) | NET | 78 (48 healthy controls) | Significant diagnosis interaction for NET G1287A polymorphism in MDD. |
| (140) | DRD4, TPH, MAO-A, and 5-HTTLPR | 134 nuclear families with mood disorders (58 with MDD) | No significant associations. |
| (141) | DRD4, MAO-A, 5-HTTLPR, DRD2, and DAT1 | United States | DRD4 5-repeat allele related to depressive symptoms among adolescents/young adults. |
| (142) | DAT1 | 264 depressed subjects | DAT1 VNTR polymorphism related to antidepressant response. |
| (143) | DAT1 | Russia | DAT1 polymorphism rs40184 related to MDD and suicidal ideation. |
| (144) | DAT1 | Chinese | No significant associations. |
| (145) | DAT1, COMT | German | 9R/9R and Val/Val genotype negatively related to Sadness score. |
| (146) | DAT1 | 1,714 subjects | DAT1 related to children's depressive symptoms. |
| (147) | DAT1 and COMT | Chinese | Interaction of DAT1, COMT, and peer acceptance predictive of adolescent depressive symptoms. |