Abstract: Described herein are compositions and methods for generating a viable cell that expresses at least one or more woolly mammoth genes. Also described herein are compositions and methods for generating an embryo, blastula, oocyte, or non-human organism that expresses one or more woolly mammoth genes.

Abstract: The present disclosure provides methods and compositions of altering a target nucleic acid sequence in a cell. The methods comprise introducing into the cell a guide RNA comprising a portion that is complementary to all or a portion of the target nucleic acid sequence, introducing into the cell a Cas9 transposase fusion protein, and introducing into the cell a donor nucleic acid sequence, wherein the guide RNA and the Cas9 transposase fusion protein co-localize at the target nucleic acid sequence, wherein the Cas9 transposase fusion protein cleaves the target nucleic acid sequence and the donor nucleic acid sequence is inserted into the target nucleic acid sequence in a site specific manner.