Functionally inactive indoleamine-2,3-dioxygenase-2 (IDO2) alleles are frequently found in familial pancreatic cancer (FPC) patients. (A) Prevalence of FPC in various Y359Stop genotypes (wild-type, heterozygous, and homozygous) in the entire Thomas Jefferson University Hospital (TJUH) cohort (FPCs and sporadic pancreatic ductal adenocarcinoma [PDA]). Spearman’s correlation test (ρ = 0.229, p < 0.05). (B) Y359Stop genotype distribution in FPC as compared with CEU (Utah residents with northern and western European ancestry) control cases. chi-square test, 2 × 3 comparison, p = 0.054. WT, wild type. (C) Rates of FPC in various R248W genotypes. Spearman’s correlation test (ρ = 0.028, p = NS) in the entire TJUH cohort (FPCs and sporadic PDA). (D) R248W genotype distribution in FPC compared with CEU control cases. Chi-square test, 2 × 3 comparison, p = NS.