The susceptibility allele was further associated with the reduced expression of PGAP3 in noninflamed ileum biopsies from the overall IBD group and with the reduced expression of ZPBP2 in noninflamed ileum biopsies from the CD group (Table 2, Figure 3), with the expression of PGAP3 reduced 1.81-fold (2 versus 0 susceptibility alleles) and that of ZPBP2 reduced 2.27-fold (1 versus 0 susceptibility alleles). Here, PGAP3 is linked to inflammatory bowel disease.