Inclusion Criteria:  Males or females ≥18 years of age at the time of informed consent. Confirmed genetic diagnosis of biallelic autosomal recessive NR2E3 mutations for Subgroup 1, autosomal dominant NR2E3 mutation or autosomal dominant RHO mutations for Subgroup 2. For the sentinel subject of Cohort 1-3, BCVA ≤ 20/160 in study eye or visual field less than 20° in any meridian, as measured by a III4e isopter (Goldmann kinetic perimetry:) or equivalent in study eye. For non-sentinel subject, BCVA ≤ 20/50 or visual field less than 20° in any meridian, as measured by a III4e isopter or equivalent in study eye. Able to perform a multi-luminance mobility testing (MLMT) using study eye, but unable to pass the MLMT at 1 lux, the lowest luminance level tested.  Exclusion Criteria:  Subject has areas of retina with thickness measurements less than 100μm as determined by spectral-domain optical coherence tomography (wide-field 45° SD-OCT). Considered unsuitable for any reason that may either place the subject at increased risk during participation or interfere with the interpretation of the study outcomes by the Investigator, or the Sponsor after reviewing medical, ocular, and psychiatric history, clinical examination, and laboratory evaluation, as determined by the Investigator, i.e., inability to fixate, high myopia ≥10 diopters, glaucoma, medium haze, other retinal pathologies, etc. Previous treatment with a gene-therapy or cell therapy product. Previous treatment with any investigational drug or device within one year. Any contraindications for subretinal injection. Any intraocular surgery within 6 months. Breast-feeding, pregnancy, sperm donation or inability to practice strict contraception within the Treatment Observation Period. (Section 8.3.2). Any medical condition with life expectancy < 6 years.