Fen1^tm2Klng

Site directed mutagenesis followed by homologous recombination was used to modify the coding sequence of exon 2 creating an amino acid substitution of aspartic acid for glutamic acid at position 160 (E160D). This mutation alters the single active residue site in the nuclease core domain. A neo cassette was also inserted downstream of exon 2 for selection purposes. (J:138901)