Promoter/enhancer replacement by genome editing for crop improvement

Genome editing is a technology that enables targeted mutagenesis. Notably, site-directed nucleation (SDN)-1 genome editing, which does not involve the incorporation of foreign DNA sequences and can introduce the same mutations as naturally occurring mutations, is not subject to genetically modified organism (GMO) regulations in many countries if transgenes are segregated out. This makes it an attractive strategy for crop improvement. Multiple DNA double-strand breaks introduced via genome editing may lead to inversions or translocations. If these genomic alterations involve promoter regions, a promoter/enhancer replacement may occur, thereby altering target gene expression as desired. Because conventional SDN-1 genome editing primarily induces loss-of-function mutations, promoter/enhancer replacement by genome editing (PERGE) represents a new paradigm in genome editing for crop improvement.