Analysis of CagA, VacA and IceA genotypes of colonized Helicobacter pylori and Interleukin-1 receptor antagonist (IL-1RN) gene polymorphism among dyspepsia patients

Pro-inflammatory Interleukin-1 receptor antagonist (IL-1RN) gene polymorphism and high risk Helicobacter pylori virulence factors in combination plays an important role in the outcome of H. pylori associated diseases, which can even lead to gastric cancer. The purpose of this study was to analyze the prevalence of high risk host and bacterial factors such as IL-1RN gene variable number tandem repeat (VNTR) polymorphism and cagA, vacA and iceA genotypes among a group of H. pylori infected dyspepsia patients from Kozhikode area of Kerala state, India. Mucosal biopsies from fourty two randomly selected dyspepsia patients infected with H. pylori, as determined by rapid urease test (RUT) and glmM gene specific PCR, were used in this study. The high risk bacterial virulence factors such as vacA,cagA,iceA1 and iceA2 genotype status of colonized H. pylori and the high risk host proinflammatory IL-1RN*2/2* allele status were examined by PCR methods. The high risk vacAs1/cagA/IL1RN*2/*2 genotype combination was found in six patients (14%), vacA s1/cagA/IL-1RN*1/*1 in three patients (7%) and vacAs1/cagA/IL-1RN*1/*2 in seven patients (16%). In addition, analysis of allelic variation of iceA gene of H. pylori, such as iceA1 and iceA2 genotype, in colonized patients has revealed the co-existence of both iceA1 and iceA2 strains among 31% of patients included in this study.