Recent research has demonstrated associations between statin use, KIF6 719Arg carrier status, and cholesterol levels and amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease (AD) patients. The association between 719Arg carrier status with homocysteine (tHcy) and c-reactive protein (CRP) levels in aMCI and AD has not been previously investigated. Data from 175 aMCI and AD patients were used for the analysis. 719Arg carriers had significantly lower levels of tHcy than noncarriers ( ). No significant difference in CRP levels between 719Arg carriers and noncarriers was present ( ). Logistic regression yielded no significant effect for 719Arg status on CRP [OR = 1.79 (0.85, 3.83), ] but did demonstrate a significant effect for tHcy [OR = 0.44 (0.23, 0.83), ] after adjusting for ApoE carrier status, age, gender, and statin use. This study is the first to explore the relationship between KIF6 719Arg carrier status with tHcy and CRP levels. 719Arg carriers were more likely to have normal tHcy levels after adjusting for ApoE status, age, gender, and statin use. These results suggest that the KIF6 gene might influence cardiovascular pathways associated with AD. 1. Introduction The KIF6 gene is one of several molecular components involved in the intracellular transport of protein complexes, membrane organelles, and messenger ribonucleic acid along microtubules [1]. There are three polymorphisms of the KIF6 gene which include Arg/Arg, Trp/Arg, and Trp/Trp. Individuals carrying the Arg/Arg or Trp/Arg polymorphisms are classified as 719Arg carriers and have been linked to an increased risk for cardiovascular disease [1–6] relative to 719Arg noncarriers (Trp/Trp). Some of these studies also demonstrated a greater lipid lowering response from statin therapy among 719Arg carriers when compared to noncarriers [1–4]. Others have found no association between 719Arg carrier status and cardiovascular outcomes [7, 8]. A recent study by Sabbagh et al. [9] found that positive 719Arg carrier status combined with statin use was associated with lower total cholesterol (TC) and lower low density lipoprotein (LDL) levels in a sample of amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease (AD) patients. In terms of disease risk, cholesterol levels and statin use have garnered significant attention from aMCI/AD researchers [10–13]; however, homocysteine (tHcy) [14, 15] and c-reactive protein (CRP) [16–18] have also been implicated as risk factors for aMCI and AD. Troen and Rosenberg [19] describe several studies that established elevated tHcy as a risk
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