From SNPedia
rs669 is a SNP in the alpha-2-macroglobulin A2M gene. In dbSNP orientation, the rs669(A) allele encodes an isoleucine, and the rs669(G) allele encodes a valine; the SNP is also known as the Ile/Val variant.
On its own, rs669 was not seen to reproducibly and independently increase risk for Alzheimer's disease in several studies of ~200 Italian patients. However, the T-C-A haplotype of rs12316150-rs1050283-rs669 was associated with both early- and late-onset Alzheimer's disease. The majority of the disease risk from this haplotype was based on rs1050283.[PMID 18191876]
The original 2004 study of 148 Italian sporadic AD patients yielded an odds ratio for the rs669(G;G) genotype (as oriented in dbSNP orientation) of 3.81 (CI: 1.66-8.75). The presence of rs2333227(C;C), in addition to rs669(G;G), appears to synergistically increase the risk of AD to an odds ratio of 25.5 (CI: 4.65-139.75), regardless of ApoE status.[PMID 15023809]
| ? | (A;A) (A;G) (G;G) |
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