This transgene encodes a wild-type murine Prnp gene. Expression studies demonstrate that this line expresses Prnp transcripts in the brain 4- to 5 fold compared to wild-type. Expression patterns were similar to wild-type mice with the notable exception that transcript was not detected in Purkinje Cells. This transgenic construct, referred to as 'half genomic' was designed to omit a large intron in order to facilitate subsequent mutagenesis studies. Transgenic line 19 carries 30 copies of the integrated transgene.