Table 2.
Examples of genetic factors implicated in schizophrenia
| Chromosomal location | Candidate gene | Encoded protein | Major function | Reference(s) |
|---|---|---|---|---|
| 22q11 | COMT | Catechol-O-methyltransferase | Monoamine metabolism | [14-16] |
| 6p22 | DTNBP1 | Dystrobrevin binding protein 1 | Organelle biogenesis | [15,16] |
| 8p12 | NRG1 | Neuregulin 1 | Signal transduction in cell-cell interactions | [14-18] |
| 1q23.3 | RGS4 | Regulator of G protein signaling 4 | Regulation of G proteins | [15,16] |
| 7q21.1 | GRM3 | Metabotropic glutamate receptor 3 | Excitatory glutamatargic neurotransmission | [15] |
| 13q34 | G72 | D-Amino acid oxidase activator | Degradation of D-serine, involved in NMDA-type neurotransmission | [14,15] |
| 8p21.3 | PPP3CC | Catalytic subunit of protein phosphatase 3 | Regulation of dopaminergic signal transduction | [14,16] |
| 15q14 | CHRNA7 | Nicotinic acetylcholine receptor | Cholinergic synaptic transmission | [16] |
| 22q11.21 | PRODH | Proline dehydrogenase (oxidase) 1 | Proline degradation | [14,16] |
| 6p21.3-22.1 | MHC region | MHC proteins | Crucial parts in immune system | [20,21,23] |
| 2q32.1 | ZNF804A | Zinc finger protein 804A | Not fully characterized | [19,22] |
| 18q21.2 | TCF4 | Transcription factor 4 | Involved in nervous system development | [21,23] |
| 11q24.2 | NRGN | Neurogranin | Postsynaptic protein kinase pathway | [23] |
| 1p21.3 | MIR137 | MicroRNA 137 | Not fully characterized | [21] |
| Copy number or structural variants | ||||
| Chromosomal location | Representative genes in the region | Reference(s) | ||
| 1q21.1 | CHD1L, GPR89B, BCL9, PRKAB2 and others | [24-26] | ||
| 15q11.2 | CYFIP1, TUBGCP5, NIPA1, NIPA2 | [24] | ||
| 15q13.3 | CHRNA7, KLF13, OTUD7A, TRPM1 and others | [24,26] | ||
| 16p11.2 | KCTD13, MAPK3, TAOK2, CDIPT and others | [29] | ||
| 22q11.2 | COMT, PRODH, SLC25A1, CLDN5, TBX1 and others | [26,28] | ||
MHC, major histocompatibility complex; NMDA, N-methyl-D-aspartate.