The genomic sequence containing Myh1 and the 5' end of Myh4 was inverted using sgRNAs (targeting ATGAGTGTGTGGCTAGGCAACGG, GTGGCTAGGCAACGGTTTGGGGG, ATGATTTGACAGTGAGTCAGAGG, GGGTTCTCATGCTAACACAGAGG, AAGTGAAGTGGATAACCACAGGG and CAGAATGGCAGACGGCCCTGTGG) with CRISPR/Cas9 technology. (J:322002)