This gene encodes a homeodomain-containing protein that plays a role in eye development. Mutation of this gene causes age-related macular degeneration type 6, an eye disorder resulting in accumulations of protein and lipid beneath the retinal pigment epithelium and within the Bruch's membrane. Defects in this gene can also cause cone-rod dystrophy type 11, a disease characterized by the initial degeneration of cone photoreceptor cells and resulting in loss of color vision and visual acuity, followed by the degeneration of rod photoreceptor cells, which progresses to night blindness and the loss of peripheral vision. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]