The Genome-Wide Association (GWA) study is the latest approach in the development of genetic studies and is renowned for its widespread success in identifying disease variants within the genome for various common diseases. It is a highly popular study amongst geneticists worldwide, evident from the numerous GWA studies conducted in laboratories all over the world. This paper introduces various GWA study designs currently recognized, including other aspects such as the software tools and its progress thus far. Especially, the paper reviews the genetic studies for glaucoma, an ocular disease which can lead to irreversible and permanent vision loss. Glaucomatous progression can be slowed or even halted if detected early; however, genetic information on glaucoma has not been well established yet. Therefore, by conducting a GWA study on glaucoma to find comprehensive associated genetic variants, the early detection of glaucoma through GWA may finally be seen as a possibility.