Phylogenetic analysis, based on EPIYA repeats in the cagA gene of Indian Helicobacter pylori, and the implications of sequence variation in tyrosine phosphorylation motifs on determining the clinical outcome

Abstract

The population of India harbors one of the world’s most highly diverse gene pools, owing to the influx of successive waves of immigrants over regular periods in time. Several phylogenetic studies involving mitochondrial DNA and Y chromosomal variation have demonstrated Europeans to have been the first settlers in India. Nevertheless, certain controversy exists, due to the support given to the thesis that colonization was by the Austro-Asiatic group, prior to the Europeans. Thus, the aim was to investigate pre-historic colonization of India by anatomically modern humans, using conserved stretches of five amino acid (EPIYA) sequences in the cagA gene of Helicobacter pylori. Simultaneously, the existence of a pathogenic relationship of tyrosine phosphorylation motifs (TPMs), in 32 H. pylori strains isolated from subjects with several forms of gastric diseases, was also explored. High resolution sequence analysis of the above described genes was performed. The nucleotide sequences obtained were translated into amino acids using MEGA (version 4.0) software for EPIYA. An MJ-Network was constructed for obtaining TPM haplotypes by using NETWORK (version 4.5) software. The findings of the study suggest that Indian H. pylori strains share a common ancestry with Europeans. No specific association of haplotypes with the outcome of disease was revealed through additional network analysis of TPMs.

Helicobacter pylori cagA gene Polymorphism in Patients with Gastroduodenal Diseases

“…Similar findings were reported from India and Colombia. 11,20 In contrast, these results differed from that of Korea where the East Asian type cagA (EPIYA-D) is dominant and some other countries like Malaysia and Thailand where both types of cagA (Western and East Asian) are present. 21-.23 Among 19 cagA positive cases majority (11, 57.9%) were EPIYA ABC motif followed by 5(26.3%) EPIYA ABCC, 2(10.5%) AC and 1(5.2%) AB motif.…”

“…7,10 Western type EPIYA ABC pattern present in 100% H. pylori strains isolated from patients with various gastroduodenal diseases in India. 11 The phylogenetic analysis of the 5ˊ end of the cagA gene indicates that Bangladeshi isolates are more closely related to H. pylori isolates from India and are different from isolates of East Asia. 12 As large number of populations in Bangladesh are seropositive for H. pylori so, it is important to know the number and pattern of cagA EPIYA motifs for identifying the H. pylori infected patients who tend to develop severe gastroduodenal diseases.…”

Pre–Endoscopy Screening of Helicobacter pylori Infection: Implication and Advantages

“…Hence, analysis of complete cag PAI of H. pylori isolated from saliva would be of immense importance in standardizing saliva as a reliable non-invasive diagnostic specimen and also to evaluate the type of Hp infection. cagE and cagT are found in a larger proportion of the ulcer group than in the non-ulcer group [24,25].…”

“…Non-invasive methods for the rapid diagnosis of Hp in salivary secretion of patients with various gastric diseases using 16S rRNA PCR analysis result to be very useful in pre-endoscopy screening thus showing comparable results with those obtained when biopsies are used (Table 3).Consequently saliva of infected persons serves as a reliable non-invasive alternative to detect the presence of Hp infection compared to currently diagnostic invasive tests. Tiwari et al [24] in another research also report salivary secretion as a sample suitable for detecting cag PAI (pathogenicity island) of infecting Hp correlating this with the disease status of the patients. Hence, analysis of complete cag PAI of H. pylori isolated from saliva would be of immense importance in standardizing saliva as a reliable non-invasive diagnostic specimen and also to evaluate the type of Hp infection.…”

Fecal Helicobacter pylori glmM and 16S rRNA genes correlate with serum TNF-α and IL-1β cytokine fluctuations

“…Helicobacter pylori are spiral-shaped, Gram-negative, microaerophilic bacteria with flagella that develop gastritis, gastric ulcer, and gastric adenocarcinoma, as well as are associated with primary gastric lymphoma and expansion within the glandular epithelium [1,2]. H. pylori infection often constantly causes chronic swelling, but only some of the Helicobacter strains can create ulcer more than the others.…”