The targeting vector is designed to insert a 106 kb (Chr14:73121400 - 73227703) fragment of the human PSEN1 in place of Chr12:83730110 - 83793335 of the mouse Psen1 gene. The construct includes an loxP-flanked neomycin selection cassette. In addition, there is also a PSEN1-DT (non-coding antisense RNA) in the human genome segment. The insertion disrupts Psen1 transcription. The neomycin cassette was removed by transient expression of cre. (J:101977)