OBJECTIVETo explore the genetic association between protein tyrosine phosphatase receptor type R (PTPRR) gene polymorphism and major depressive disorder (MDD) and its endophenotype.

METHODSA total of 517 unrelated MDD patients and 455 unrelated healthy subjects were recruited in this study to detect 11 single nucleotide polymorphisms (SNPs) in the PTPRR locus. They all were of the Chinese Han origin. Genotyping of SNPs was performed by matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) -based genotyping approach. The UNPHASED program was applied to analyze the genotyping data.

RESULTSOf the 11 selected SNPs, no significant allelic and genotypic association was found between MDD patients and the normal controls (corrected P > 0.05). However, analysis of haplotypes showed that the three SNPs haplotype rs1398599 (C) -rs2175711 (A) - rs4489789 (T) (P = 0.0023, OR = 1.334, 95% CI = 1.104-1.612) and four SNPs haplotype rs11178391 (C) -rs1398599 (C) -rs2175711 (A)-rs4489789(T) (P = 0.0063, OR = 1.281, 95% CI = 1.059-1.549) were associated with increased risk of MDD. Quantitative trait analysis revealed that rs2203231 in the PTPRR locus had strong allelic and genotypic association with the raw score of long-term memory (P = 0.0038 for allelic association, P = 0.0024 for genotypic association), the scaled score of long-term memory (P = 0.0057 for allelic association, P = 0.0038 for genotypic association), the raw score of short-term memory (P = 0.0027 for allelic association, P = 0.0015 for genotypic association), and the scaled score of short-term memory (P = 0.0035 for allelic association, P = 0.002 for genotypic association) in MDD patients.

CONCLUSIONThe polymorphism of PTPRR gene rs2203231 may be associated with the impairment of long-term and short-term memories in MDD patients.