Tc(HSA19*)VLDkn

The allele is created in a multi-step process by exchanging approx. 20 kb on mouse chromosome 7 stretching from and including Tomm40 to Apoe from BAC RP24-136M6 with an acceptor cassette containing PGK-hygromycin and HSV-TK flanked by loxP/lox2272 sites from C57BL/6N-derived C2(Nagy) embryonic stem cells (ES). The 5' loxP site is located downstream of Pvrl2 and the 3' lox2272 site is located downstream of the last Apoe exon (including the enhancer segment). ES cells carrying the acceptor cassette were electroporated with the exchange vectors and a plasmid carrying Cre recombinase to insert 23.77 kbp from human BAC (RP11-84C16) containing TOMM40 to APOE and the flanking sequences (including promoter and regulatory regions) followed by an FRT-flanked PGK-neo cassette and a loxP site on chr19 : 45,393,394-45,417,163 (HSA19). The modified BAC carries the 523 polyT short allele (S) on an APOE epsilon 3 backbone. APOE epsilon4 is converted to APOE epsilon3 by exchanging the APOE epsilon4 arginine (CGC) at SNP rs429358 with the APOE epsilon3 cysteine (TGC). The TOMM40 523 polyT site is modified by homologous recombination from 15 deoxythymidine residues to 30 deoxythymidine residues creating the very long (VL) allele. (J:341425)