The transgene is composed of a C57BL/6 mouse BAC (RP23-78A8). Exons 1 and 2 of Casp1 were inactivated by replacing them with a FRT-PGK-em7-Neo=FRT cassette. Flp-mediated recombination removed the neo cassette. The transgene was injected into Casp1tm1Sesh embryos. The pound symbol (#) is used when no line is specified and/or lines are pooled.