Stargardt disease (STGD), a hereditary macular dystrophy, is characterized by the presence of yellowish flecks within the retinal pigment epithelium (RPE), ultimately culminating in macular atrophy. Typically manifesting in childhood and adolescence, STGD leads to progressive central vision loss and mild dyschromatopsia. Fundoscopic examination may reveal pale yellow lesions exhibiting a characteristic gold foil-like sheen, accompanied by yellow-white spots surrounding the posterior pole. In advanced stages, atrophy of the RPE, photoreceptors, and choriocapillaris is observed. This bilateral and typically synchronous condition affects both eyes with comparable incidence across sexes, estimated between 1/8,000 and 1/13,000. STGD is predominantly an autosomal recessive disorder, with mutations in the ABCA4 gene accounting for approximately 95% of cases. ABCA4 encodes a retina-specific ABC transporter protein crucial for the clearance of retinal derivatives and toxic metabolites generated during rhodopsin photobleaching. Consequently, ABCA4 mutations result in the accumulation of these cytotoxic substances, triggering apoptosis of both RPE and photoreceptor cells and ultimately driving retinal degeneration. Notably, ABCA4 mutations have been implicated in a spectrum of retinal diseases, including STGD, cone-rod dystrophy (CRD), age-related macular degeneration (AMD), and retinitis pigmentosa (RP), with the specific clinical phenotype correlating with the nature and severity of the ABCA4 mutation. This strain is an Abca4 gene knockout (KO) mouse model. Gene-editing technology was used to delete the protein-coding sequence of the Abca4 gene (the homolog of the human ABCA4 gene) in mice. Previous studies have demonstrated that Abca4 KO mice exhibit delayed dark adaptation following photobleaching and a slow progression of photoreceptor degeneration^[1]. Homozygous Abca4-KO mice are viable and fertile.

Abca4 is located on chromosome 3 of mice. Nuclease Technology was used to design sgRNA; Abca4 knockout mice were obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Abca4 is located on chromosome 3 of mice. Nuclease Technology was used to design sgRNA; Abca4 knockout mice were obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Rhox10 is located on chromosome X of mice. SgRNA and ssDNA will be designed using Nuclease Technology; Rhox10 conditional knockout mice will be obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm will be collected for cryopreservation.

Zfp800 is located on chromosome 6 of mice. Nuclease Technology will be used to design sgRNA; Zfp800 knockout mice will be obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Abca4 is located on chromosome 3 of mice. SgRNA and ssDNA were designed using Nuclease Technology; Abca4 conditional knockout mice were obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.