From: DNA methylation in peripheral tissue of schizophrenia and bipolar disorder: a systematic review
Summary | Genetic loci | Results | Gene expression status | Group | |||||
---|---|---|---|---|---|---|---|---|---|
Loci | References | Â | Candidate loci | Global DNA | Â | Â | |||
Serotonin | [49] | 5-HTR1A | a | Â | Â | Â | Â | - | SZ, BD |
 | [51] | HTR1A |  |  |  | c, a |  | Decrease (in SZ) | SZ, BD |
 | [50] | HTR2A |  |  | d |  |  | Increase (SZ & BD) | SZ, BD |
 | [48] | SLC6A4 |  |  |  | c |  | Decrease (S/S genotype only) | BD |
 | [37] | HTR1E |  |  |  | c |  | - | SZ |
 | [34] | 5-HTT |  |  |  |  | d | - | SZ |
Glutamate | [21] | GRIA2 | Â | Â | Â | c | Â | - | SZ |
 | [29] | GMR2 GMR5 GMR8 GRIA3 | a |  |  |  |  | Increase (GRM2, GRM5 & GRIA3 only) | SZ |
BDNF | [44] | BDNF exon 1 promoter | a | Â | Â | Â | Â | - | BD-II |
 | [45] |  | a |  |  |  |  | Decrease (BD-II only) | BD-II |
 | [43] |  |  |  | d |  |  | - | BD |
 | [25] | BDNF promoter I | a |  |  |  |  | - | SZ |
 | [30] | BDNF promoter |  |  |  | c |  | Increase | SZ |
 | [25] | BDNF promoter IV |  |  | d |  |  | - | SZ |
Dopamine | [30] | DAT1 | a | Â | Â | Â | Â | No difference | SZ |
 | [37] | SLC6A3 |  | b |  |  |  | - | SZ |
 | [27] | SLC18A2 |  |  |  | c |  | - | SZ |
COMT | [52] | MB-COMT | Â | b | Â | Â | Â | Increase (SZ & BD) | SZ, BD |
 | [34] | S-COMT | a |  |  |  |  | - | SZ |
 | [51] | COMT |  |  |  | c, b |  | - | SZ, BD |
 | [37] | COMTD1 promoter |  |  |  | c |  | - | SZ |
 | [36] | S-COMT promoter |  |  | d |  |  | - | SZ |
RELN | [20] | RELN intron 1 | Â | Â | Â | c | Â | - | SZ |
 | [21] | RELN promoter |  |  | d |  |  | - | SZ |