Meta-Analysis of Ubiquilin1 Gene Polymorphism and Alzheimer's Disease Risk

Background: Some studies have evaluated the association between the Ubiquilin 1 (UBQLN1) gene UBQ-8i polymorphism and Alzheimer's disease (AD). However, the results remain uncertain. We carried out a meta-analysis to derive a more comprehensive estimation of this association. Material/Methods: Case-control studies were identified by searching databases of PubMed, EMBASE, Web of Science, CNKI, CBM, Wanfang, and VIP. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. Results: The UBQ-8i polymorphism was significantly associated with an increased AD risk (OR=1.15; 95% CI 1.05-1.25; P=0.002). The combination of adjusted ORs also found UBQ-8i polymorphism was significantly associated with AD risk (OR=1.15; 95% CI 1.02-1.30; P=0.02). When stratified by APOE epsilon 4 status, both APOE e4 carriers and APOE non-epsilon 4 carriers with UBQ-8i polymorphism had significantly increased AD risk (OR=1.28; 95% CI 1.05-1.56; P=0.01 and OR=1.25; 95% CI 1.04-1.50; P=0.02). In the subgroup analysis according to age, UBQ-8i polymorphism was significantly associated with LOAD risk (OR=1.17; 95% CI 1.05-1.31; P=0.005), but not with EOAD risk (OR=1.12; 95% CI 0.95-1.31; P=0.17). Conclusions: These results suggest that the UBQ-8i polymorphism is associated with AD risk.