IL1R1 and endometriosis: IL1A and IL1B both signal through the interleukin receptor (IL1R1) to regulate NF‐κB, cJUN, and p38 MAPK signaling, inducing the expression of a host of genes, including IL8.[50] Expression of IL8 (encoded by the CXCL8 gene) was also associated with endometriosis single‐cell disease risk scores, suggesting multiple risk variants may converge to modulate different components of the IL1 pathway.