The collagen type II alpha 1 chain (COL2A1) gene encodes the alpha-1 chain of collagen type II, a fibrillar collagen found in cartilage and the eye's vitreous humor. Collagen type II is closely related to the structure and strength of connective tissue and is found primarily in cartilage, vitreous humor, inner ear, and the gelatinous material (nucleus pulposus) in the central part of the intervertebral disc between the vertebrae of the spine. This strain was generated by integrating the mouse Col2a1 gene promoter-regulated codon-improved Cre recombinase (iCre) gene expression cassette into the mouse genome. This results in the conditional expression of iCre in chondrocytes, under the control of the Col2a1 promoter. When bred with mice containing a loxP site-flanked sequence, Cre recombinase-mediated deletion of the flanked sequence will occur specifically in chondrocytes in the offspring. Both homozygous and heterozygous H11-Col2a1-iCre mice are viable and fertile.

Defb47 is located on chromosome 14 of mice. SgRNA and ssDNA were designed using Nuclease Technology; Defb47 conditional knockout mice were obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Tmem219 is located on chromosome 7 of mice. Nuclease Technology will be used to design sgRNA; Tmem219 knockout mice will be obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Col2a1 is located on chromosome 15 of mice. Nuclease Technology will be used to design sgRNA; Col2a1 knockout mice will be obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Col2a1 is located on chromosome 15 of mice. SgRNA and ssDNA were designed using Nuclease Technology; Col2a1 conditional knockout mice were obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.