Assessment of TREM2 rs75932628 association with Parkinson's disease and multiple system atrophy in a Chinese population

Although rs75932628 in triggering receptor expressed on myeloid cells 2 (TREM2) was shown to increase the risk for Alzheimer's disease, there is no agreement on the association between this variant and the risk for Parkinson's disease (PD). Considering the overlapping of clinical manifestation and pathologic characteristics of PD and multiple system atrophy (MSA), we conducted a large-sample study to investigate the associations between this variant and these two neurodegenerative diseases in a Chinese population. A total of 1216 PD, 406 MSA patients, and 869 healthy controls were included. All cases were genotyped for the Single Nucleotide Polymorphisms (SNP) using Sequenom iPLEX Assay technology. The rs75932628-T variant of the TREM2 gene was not identified in PD patients and controls. The genotype frequency of rs75932628-T SNP in MSA patients was 0.25 % (1/406). However, no significant correlation was identified between this variant and the risk for MSA. TREM2 rs75932628 is unlikely to play a major role in the pathogenesis of these neurodegenerative diseases. Our findings argue against a generalized immune dysfunction triggered by the variant in the TREM2 gene.