This review provides an update on genome-wide association studies in periodontitis. Studies in populations with European ancestry have dominated the landscape of periodontitis genetics studies but, increasingly, studies in Asian populations are being reported. The review also summarizes evidence for suggested associated genetic variations. The loci associated with genome-wide association studies consist of noncoding variations, many of which are predicted to modulate levels of gene expression. In this article, the biological functions of the genes that are nearest to the associations and their implications for disease etiology are also examined. A major challenge in the genetics of periodontitis is identification of the causal variant(s) underlying associations with periodontitis, elucidation of the molecular mechanisms that are potentially affected by the associated variants, and understanding how they contribute to disease phenotypes and traits. This will allow emerging medical initiatives to make clinical use of genetic discoveries. Large collaborative studies, across research centers and across subspecialties and disciplines, will be required to realize the promise of genetic discovery in periodontitis.