PRDM1 and hyperinsulinemic hypoglycemia, familial, 4: To identify and/or validate whether the immune diseases and disorders potentially modulated by IL-21 are linked with Blimp-1 deficiency, we first subjected genes selected from ATAC-Seq for differential chromatin accessibility and RNA-Seq data for expression levels in CKO and control T cells to Ingenuity Pathway Analysis (IPA).