In ESCS, dysfunction of the NR2E3 gene will lead to loss of rod function and an excess of S-cones (short-wavelength) at the expense of M-cones (medium-wavelength) and L-cones (long-wavelength).1,2 The earliest symptom of ECSC is nyctalopia, and in some patients, a decreased visual acuity and/or nystagmus is seen. Here, NR2E3 is linked to enhanced S-cone syndrome.