Recently, the immune-related gene encoding purinergic receptor P2X, ligand-gated ion channel, 7 (P2RX7) has been genetically associated with major depressive disorder and bipolar disorder.
A non-synonymous single nucleotide polymorphism, rs2230912 (P2RX7-E13A, G allele) and a microsatellite marker NBG6 were both previously found to be associated with bipolar disorder (P=0.00071 and 0.008, respectively). rs2230912 has also been found to show association with unipolar depression.
The single nucleotide polymorphisms FKBP5:rs1360780, BDNF:rs6265 (Val66Met), P2RX7:2230912 (Gln460Arg) and CACNA1C:rs1006737 were genotyped in DNA from 457 depression cases (major depression, dysthymia, and mixed anxiety depression) and 2286 healthy controls with no symptom of psychopathology.
Comprehensive investigation of the P2X7RGln460Arg missense mutation (rs2230912), which has been associated with major depression and bipolar disorder, has substantially contributed to validate P2X7R as a potential genetic risk factor.