The present invention provides isolated promoters, transgene expression cassettes, vectors, kits, and methods for treatment of genetic diseases that affect the cone cells of the retina. The present invention features, in a first aspect, a nucleic acid comprising a portion of the cone cell specific promoter PR 2.1. In one embodiment, the nucleic acid comprises the sequence SEQ ID NO: 4. In another embodiment, PR2.1 is truncated at the 5' or the 3' end. In one embodiment of the above aspects, the promoter is capable of promoting CNGB3 expression in S-cone cells, M-cone cells, and L-cone cells. In another embodiment of the above aspects, the promoter is capable of promoting CNGA3 expression in S-cone cells, M-cone cells, and L-cone cells. In yet another embodiment of the above aspects, the promoter is capable of promoting GNAT2 expression in S-cone cells, M-cone cells, and L-cone cells.
