Only three genes were upregulated in POI, including IFITM1, JUN, and PPBP. Enrichment analysis showed that the upregulated genes were mainly enriched in B cell receptor signaling pathway, while the downregulated genes were mainly enriched in immune pathways including allograft rejection, autoimmune thyroid disease, and RIG−I−like receptor signaling pathway (Figure 7F). Here, IFITM1 is linked to autoimmune thyroid disease.