Rr70^tm1Alb

Exons 3-9 of the Hprt minigene, a loxP site and a puromycin resistance gene cassette were inserted 13 kb upstream of exon 1. The mutation also included a 6 kb genomic duplication of the 7-13 kb upstream sequence. Maternal inheritance of this allele leads to Snrpn imprinting defects, leaving the maternal Snrpn allele unmethylated. (J:105289)