Once considered primarily a disease of aging caused by unknown environmental influences, the notion that heritable factors could significantly contribute to the pathogenesis of sporadic glaucoma has rapidly gained traction. In part, this is due to the rapid and definitive identification of genes with strong effects on familial, earlier onset forms of glaucoma. Although the endpoint of glaucoma is irreversible optic nerve damage accompanied by blindness, the initial inciting trigger could differ. To this end, well-powered genome-wide association studies have each been conducted for primary open-angle glaucoma, primary angle-closure glaucoma, along with exfoliation syndrome and glaucoma. Each of these studies has revealed sets of significantly associated genetic loci implicating biological pathways that do not overlap between the forms of glaucoma. Although substantial biological insight has been gained from their identification, much further work remains to definitively link the implicated genetic variants with glaucoma causation. It is also hoped that the genetic findings could point us to potential routes of therapy beyond that of intraocular pressure–lowering medications or surgery.