Pitx1^em1.1Chalu

CRISPR/Cas technology was employed to introduce loxP sequences flanking a 13-kb enhancer residing 132 kb 3' of the promoter (Pitx distal enhancer or PDE), shown via chromatin conformation capture (3C) and chromosome conformation capture-on-chip (4C) analyses to interact topologically with the target gene. The floxed sequence was deleted by Cre recombinase. The deleted sequence spans Chr 13 nucleotides 56,055,928 through 56,068,947. In heterozygous mutant embryos at E11.5, Pitx1 expression is reduced by 15% in the hindlimb and by 39% in the mandibular arch. (J:94077, J:264122)