Generation of human leukocyte antigen-homozygous human induced pluripotent stem cells. Homo sapiens strain:iPS cell

Homologous recombination is an efficient tool of genome engineering. We applied the chromosome crossing-over(CO) event according to the homologous recombination for generating intentional HLA region homogenization. The combination of allele-specific double strand breaks by CRISPR/Cas9 and suppression of transcripts or proteins derived from the Bloom syndrome (BLM) gene is required for such generation. In this study, our phenotype of interest is recombination induced by CRISPR/Cas9 under the reduction of BLM repression. Using genotypes of SNP markers, we found extensive individual variation in the number of recombination events in the hiPS cells. To detect CO events in hiPSCs, we used Infinium Omni5-4 BeadChip for the analysis of the SNPs copy number of hiPSC-BLM+/+, hiPSC-BLMtet/tet, AAVS1 cNP/+, Â hiPSC-BLMtet/tet;AAVS1 cNP/+, DOX(+)9M CRISPR(+), hiPSC-BLMtet/tet;AAVS1 cNP/+;DOX(-), ML216 (+)9M CRISPR(+),hiPSC-BLM+/+;ML(216), and HLAI-III-CRISPR(+). Data were analyzed using the Illumina GenomeStudio.