In this study, the expression of IER3 in SSCs is closely related to the development of CRC, involving it in regulating the cell cycle, cell proliferation, and apoptosis through pathways like FOS proteins and NF-κB. MR analysis shows that changes in IER3 expression correlate with CRC risk, highlighting its potential role in tumor biology. The gene discussed is FOS; the disease is colorectal carcinoma.