Background: We investigated the association between CRP variants and chronic gastritis in H. pylori-infected patients at the allele, genotype, and haplotype levels. This was also assessed according to serum hs-CRP levels. Methods: Study subjects consisted of 77 H. pylori-infected patients and 96 H. pylori-negative controls. Genotyping of the CRP rs1572970, rs876537, rs2794520, rs2808630, rs1130864, rs1417938, rs7553007, and rs4285692 variants were analyzed by real-time PCR. Results: Significantly higher MAF and increased risk of chronic gastritis were associated with rs1130864, rs1417938, and rs7553007, which persisted after controlling for key covariates. Significant differences in the genotype distribution of rs1130864, rs1417938, and rs7553007 were also seen between H. pylori-infected patients and healthy controls. Increased risk of H. pylori-associated chronic gastritis was associated with carriage of rs1130864 C/T, and more with T/T genotype carriers, as well as with rs1417938 T/A and A/A genotype carriers. Functionally, the distribution of rs1130864 and rs1417938 genotypes were significantly different between H. pylori-infected patients and controls in the low hs-CRP (<6 mg/L) group. CRP haplotype analysis identified Block 1 (rs1572970, rs876537, rs2794520), and Block 2 (rs2808630, rs1130864, rs1417938) associated with H. pylori infection. Haplotypes ACC (Block 1) and TTA and TTT (Block 2) were positively associated with H. pylori-associated chronic gastritis with low hs-CRP levels. Conclusion: Altered serum levels of hs-CRP, stemming in part from the presence of specific genetic variants in CRP gene, modulate the risk of H. pylori infection.
