The triplet CGG in exon was replaced by a TGT resulting in the replacement of an arginine with a cysteine at position 155 (R155C) and a floxed neo cassette was inserted in intron 4. Cre mediated recombination removed the neo cassette. The remaining loxP site is located further upstream than in mice carrying Vcp tm1.1Ccrs to avoid the splicing issue present in this allele. (J:263736)