Leber's congenital amaurosis (LCA) is a group of inherited retinal diseases with severe visual impairment. The main symptoms of LCA are loss of visual acuity, nystagmus, and decreased or absent light reflexes in the optic rods and cones at birth or several months after birth. Approximately 16% of LCA is caused by mutations in the RPE65 gene. In the visual cells vitamin A aldehyde (retinal) and opsins form the retinoid, and vitamin A aldehyde absorbs light and isomerizes to all-trans-retinal, causing a change in retinal conformation and initiating the neural impulses to the brain that lead to vision. During the breakdown and resynthesis of the retinal, a portion of vitamin A aldehyde is consumed and is mainly replenished by vitamin A (retinol) in the blood. The retinoid isomerase encoded by the RPE65 gene is present in the retinal pigment epithelium (RPE) of the retina, and the RPE65 protein plays a key role in the visual process by participating in the conversion of vitamin A to vitamin A aldehyde and the re-production-of-retinal-photoreceptor pigments, and is, therefore, a key molecule in the conversion and transmission of light signals by the retina ^[1]. Mutations in the RPE65 gene can lead to further degeneration of the neural retina and RPE cells, resulting in irreversible blindness. Mutations in multiple alleles of RPE65 have been found to destroy optic nerve cells and lead to type II Leber's congenital amaurosis (LCA2) and early onset severe retinal dystrophy (EOSRD), ultimately leading to complete blindness ^[1-3]. This product is a mouse Rpe65 knockout model that uses gene editing technology to knock out the homolog of the human RPE65 gene in mice. The deletion of Rpe65 gene expression in mice resulted in disruption of RPE cell function, apoptosis of photoreceptor cells, disorganization of the outer segmental discs of optic rods, and quenching of optic rod waveforms, causing severe retinal degeneration.

Leber congenital amaurosis (LCA) is a group of inherited retinal diseases accompanied by severe visual impairment. The main symptoms of this disease are vision loss at birth or within a few months after birth, nystagmus, and weakened or absent light reflexes of rods and cones. Approximately 16% of LCA cases are caused by mutations in the RPE65 gene. In visual cells, vitamin A aldehyde (retinal) combines with opsin to form visual pigments. After vitamin A aldehyde absorbs light, it is isomerized to all - trans - retinal, which causes a conformational change in rhodopsin and initiates nerve impulses to the brain, thus forming vision. During the decomposition and resynthesis of rhodopsin, a portion of vitamin A aldehyde is consumed and is mainly replenished by vitamin A (retinol) in the blood.The retinoid isomerase encoded by the RPE65 gene is present in the retinal pigment epithelial cells (RPE) of the retina. The RPE65 protein plays a crucial role in the visual process. It participates in the conversion of vitamin A to vitamin A aldehyde and the regeneration of retinal photoreceptor pigments, so it is a key molecule for the conversion and transmission of light signals in the retina^[1]. Mutations in the RPE65 gene can lead to further degeneration of the neural retina and RPE cells, resulting in irreversible blindness. Multiple allelic mutations of RPE65 have been found to damage optic nerve cells and cause type II Leber congenital amaurosis (LCA2) and early - onset severe retinal atrophy (EOSRD), ultimately leading to complete blindness^[1-3].
This model is a mouse Rpe65 gene point - mutation model. Using gene - editing technology, a p.R44*(CGA to TGA) point mutation was introduced into the mouse Rpe65 gene, which led to abnormal expression of the mouse Rpe65 protein. This caused phenotypes such as damage to RPE cell function, apoptosis of photoreceptor cells, disordered arrangement of rod outer segment membrane discs, and extinction of rod waveforms, resulting in severe retinal degeneration.

The TGA stop codon was replaced with P2A-CreERT2 cassette. CreERT2 recombinase is expressed under the regulatory control of Rpe65 gene elements. This model is a Tamoxifen-inducible Cre mouse, and when crossed with mice containing loxP sites, the offspring mice are expected to undergo sequence recombination between loxP sites mediated by Cre recombinase in Rpe65-positive cells following Tamoxifen induction.

Sv2b is located on chromosome 7 of mice. Nuclease Technology was used to design sgRNA; Sv2b knockout mice were obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Olfml2a is located on chromosome 2 of mice. SgRNA and ssDNA were designed using Nuclease Technology; Olfml2a conditional knockout mice were obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Rpe65 is located on chromosome 3 of mice. Nuclease Technology will be used to design sgRNA; Rpe65 knockout mice will be obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Rpe65 is located on chromosome 3 of mice. SgRNA and ssDNA will be designed using Nuclease Technology; Rpe65 conditional knockout mice will be obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm will be collected for cryopreservation.