Published studies revealed that the microtubule-associated protein tau (MAPT) gene polymorphisms increased Alzheimer's disease (AD) risk; the associations of 4 single nucleotide polymorphisms (SNPs, rs242557G/A, rs2471738C/T, rs3785883G/A and rs1467967A/G) of the MAPT gene with AD risk, however, remain inconclusive.
Furthermore, a significant association of SNP rs2471738 with AD risk was found under all the four models (allelic: OR = 1.11, 95% CI = 1.01, 1.20, P = 0.021; dominant: OR = 1.10, 95% CI = 1.00, 1.21, P = 0.046; recessive: OR = 1.18, 95% CI = 1.05, 1.32, P = 0.004; additive: OR = 1.20, 95% CI = 1.07, 1.34, P = 0.002) models.
This study demonstrated that different variants in MAPT were associated with AD (rs2471738: OR= 1.04, 95%CI = 1.00 - 1.09; H2: OR = 0.94, 95% CI = 0.91 - 0.97), PD (H2: OR = 0.76, 95% CI = 0.74 - 0.79), PSP (rs242557: OR = 1.96, 95% CI = 1.71 - 2.25; rs2471738: OR = 1.85, 95% CI = 1.
Subjects carrying both the tau (intron 9, rs2471738) T allele (CT and TT genotypes) and the LRP1 (exon 3, rs1799986) T allele (CT and TT genotypes) had a 6 times higher risk of developing AD than subjects without these risk genotypes (odds ration = 6.20, 95% confidence interval = 1.74-22.05, p = 0.005), and this genetic interaction was observed in either the presence or the absence of the APOE epsilon4 allele.