Fig. 1: Generation of Makassar KI Townes mouse via CRISPR-mediated HDR.

Gene architecture of the chromosome 7 locus in the Townes mouse containing Human HBB genes63. Endogenous mouse genes are highlighted with teal bars with their respective gene names. Human HBG1 (5675 bp) and human HBB (4113 bp) tandem sequences, containing intact human genomic 5′ promoter and 3′ flanking regions highlighted in yellow are replacing murine Hbb-bmaj and Hbb-bmin. Intended knock in nucleotide substitutions to generate Makassar β globin (E6A, codon underlined) in exon 1 of HBB are highlighted in red. The gRNA spacer regions used to generate KI are shown in blue and green. Silent, synonymous mutations introduced with DNA donor oligo template to prevent re-cutting are indicated in bold black.