In a systematic explorative study of genetic patterns on chromosome 19, we discovered a pattern comprised of 23 SNP alleles that is significantly associated with late-onset Alzheimer’s disease (AD). This association is validated using two independent data sets. The pattern includes THOP1, which has a long and disputatious relationship with AD. It also spans SLC39A3 and SGTA and is upstream from DIRAS1. We utilized population data to observe the frequencies of this genetic pattern for 11 different ancestries and note that it is highly common for Europeans and relatively infrequent for Africans. This research provides a distinct genetic signature for AD risk as well as insights into the complicated relationship between this disease and THOP1.