DETECTION OF P53 and Bax genes ASSOCIATED WITH HELICOBACTER PYLORI INFECTION

Abstract

H. pylori is considered one of the most common human pathogen worldwide, with infection rates much higher in developing countries than in developed nations. The aim of this study is the investigation of some candidate genes include P53 and Bax genes mutation associated with H. pylori infection and study the role of H. pylori virulence genes on the induction of P53 and Bax genes mutation. The results show a total of 92 gastric biopsies gave positive results for the presence of H. pylori diagnosed by molecular technique. Only (49) cag a positive H. pylori strains obtain from gastric biopsy of patient suffering from H. pylori infection which also harboring cag E and vacA genes. Single Strand Conformation Polymorphism (PCR-SSCP) technique used to identify mutations in the p53 gene in several exons. Where 16 alterations in exon E5A, 19 alterations in exon E5B6A, 17 alterations in exon E7 and only two in exon E6B; but no alteration was appeared in exon E8 of P53 gene. In the same way, PCR-SSCP analysis detected alterations in Bax gene where only 14 positive samples gave alteration in the sequence of Bax gene in exons E1, E4 and E6. Regarding to exon 1 of Bax gene, it was appeared that only 10 samples gave positive gene locus mutation. This may attribute to H. pylori which stimulate Bax mutation through its ability to produce cag A protein which has the ability to cause changing in gene sequence and function. It is concluded that p53 and Bax genes mutation is important tool in the screening of genetic alteration associated with H. pylori infections.