P2RX7 and major depressive disorder: For example, the TT genotype at rs2298383 SNP in A2A receptor predicts lower risk of depression compared to the CC or CT genotypes.196 The rs2230912 polymorphism also causes a Gln460Arg mutation in P2X7 receptor, which is associated with depression.197 These SNPs are believed to serve as potential indicators for early risk assessment of depressive disorders.