%0 Journal Article
%T PCR-based genotyping of Helicobacter pylori of Gambian children and adults directly from biopsy specimens and bacterial cultures
%A Ousman Secka
%A Martin Antonio
%A Mary Tapgun
%A Douglas E Berg
%A Christian Bottomley
%A Vivat Thomas
%A Robert Walton
%A Tumani Corrah
%A Richard A Adegbola
%A Julian E Thomas
%J Gut Pathogens
%D 2011
%I BioMed Central
%R 10.1186/1757-4749-3-5
%X Virulence genes were amplified in 127 of 190 cases tested (121 adults and 6 children); each of 60 bacterial cultures, and 116 from DNA extracted directly from biopsies. The proportion of biopsies that were cagA+, the ratio of vacAs1/s2, and vacAm1/m2, and the proportion of mixed strain populations in individual subjects changed with age. Strains lacking virulence cagA and vacA genes and with apparently homogeneous (one predominant strain) infections were more common among infants than adults.In order to detect the range of bacterial genotypes harbored by individual patients, direct PCR proved slightly superior to isolation of H. pylori by biopsy culture, but the techniques were complementary, and the combination of both culture and direct PCR produced the most complete picture. The seemingly higher virulence of strains from adult than infant infections in The Gambia merits further analysis.Helicobacter pylori chronically infects over 50% of people worldwide, causes gastritis and sometimes gastric or duodenal ulceration, and increases the risk of gastric cancer [1,2]. Infection also contributes to other maladies such as malnutrition among the very poor, iron deficiency anemia, and susceptibility to other food and water borne pathogens, especially in developing countries, including The Gambia [3,4]. The prevalence of H. pylori infection is particularly high in developing countries including The Gambia [5-7]. H. pylori, because it is a fastidious micro-aerobic bacterium, it is technically difficult to grow and maintain for molecular biologic research in poorly resourced laboratories in Africa. These challenges coupled with the uniqueness of genotypes of African strains and special features of human physiology and environment in this continent limit our understanding of the spectrum of H. pylori-associated diseases and how this is affected by bacterial genotype in Africa [8,9]. So extensive efforts have been made to determine an optimum method for PCR-based genotyping o
%K Genotyping
%K Helicobacter pylori
%K biopsy specimens
%K bacterial cultures
%U http://www.gutpathogens.com/content/3/1/5