Quantitative trait locus mapping for interleukin-1b release after inflammasome priming and activation was performed on bone marrow-derived macrophages (BMDM) from an AKRxDBA/2 strain intercross.  The strongest associated locus mapped very close to the Pycard gene on chromosome 7, which codes for the inflammasome adaptor protein apoptosis-associated speck-like protein containing a CARD (ASC).  The DBA/2 and AKR Pycard genes only differ at single nucleotide polymorphism (SNP) in their 3’ untranslated region (UTR).  DBA/2 vs. AKR BMDM had increased levels of Pycard mRNA expression and ASC protein, and increased inflammasome speck formation, which was associated with increased Pycard mRNA stability without an increased transcription rate.  CRIPSR/Cas9 gene editing was performed on DBA/2 embryonic stem cells to change the Pycard 3’UTR SNP from the DBA/2 to the AKR allele.  This single base change significantly reduced Pycard expression and inflammasome activity after cells were differentiated into macrophages due to reduced Pycard mRNA stability.

rQTL software was used for the QTL analysis, with details provided in the manuscript.

Other data was derived from cell biology, biochemistry, and molecular biology studies using standard methods as provided in the manuscript.