CCL3 and Alzheimer disease: Note that we observed a significant association between CCL3 and AD in the Eastern cohort of Han Chinese, even after the Bonferroni correction (p = 4.35 × 10−4), but this association was weakened in the combined Han Chinese sample (p = 0.008; Additional file 1: Table S2), suggesting that population heterogeneity may exist even between our two cohorts under study.