This region spans five protein-coding genes: ALCAM, CBLB, BBX, CCDC54, and CD47. Secondary analyses indicated that Native American ancestry at the lead SNP of each LD-block was associated with a protective effect against AD risk (OR 0.58–0.66; P < 3.24E-04; Additional file 2). The gene discussed is CCDC54; the disease is Alzheimer disease.