Genetic polymorphism relationship of four SNP in beta defensins genes 1 and 2 with susceptibility and effect of triple therapy of Helicobacter pylori infection in Iraq

Abstract Human β-defensins (HBD), an antimicrobial peptide encoded by the (DEFB) gene. In humans they play a significant role in Helicobacter pylori immunological responses to. Four variants in β-defensins 1 and 2 genes (rs1800972 C/T, rs1047031 C/T, rs2740090 C/T and rs2740091 G/A) were included in a H. pylori patients in Iraq (80 Recurrent H. pylori infection and 80 Treated H. pylori patients). To determine these variants, we used polymerase chain reaction with tetra-primers amplification and refractory mutation system. Logistic regression of rs2740090 showed the allele and genotypes has a significant association with Recurrent H. pylori patients' susceptibility. Regarding rs1800972, T allele and CT genotype were significantly associated with an increased possibility of recovery from H. pylori infections, but the highest frequencies was found in Treated H. pylori patients for alleles in rs2740091. For SNP rs1047031, alleles and genotypes no significant difference was found. Tetra-locus haplotype (rs1800972, rs1047031, rs2740090 and rs2740091) revealed that (C-G-C-C and C-G-C-T) significantly elevated the haplotype frequency in Treated H. pylori patients. Moreover, the rs2740090 variant was associated with a Recurrent H. pylori patients' susceptibility. The overall result can lead to final conclusion that some of genetic polymorphisms in immune gene can play a role in drug susceptibility and thus we can predict the right dose and drug for treatment of person with specific genotype.