Informative sites, which are defined as those with at least two variants at a particular site and more than one isolate for each base variant,

were extracted from output generated by MULTICOMP and examined using Microsoft EXCEL. Total base changes at each informative site present in each population were summed and formed a 2 × 2 table for Fisher’s Exact test using SPSS (SPSS Inc, Chicago, IL). For those informative sites that have more than two variants, the least frequent base was removed and treated as a missing value. The probability Selleck SB-715992 of each site generated by SPSS was adjusted using Dunn-Sidak correction: α’ = 1 – (1 – α)1/p , where α’ represent adjusted probability, α represent the significance value (0.05 used in this study) and p represent the total number of comparisons. The GenBank accession numbers for the sequences reported in this study are FJ846683 – FJ847228. Acknowledgements This study was supported by a University of New South check details Wales Goldstar award and the Cancer Council of New South Wales. We thank

Heather Schmidt for providing some of the DNA samples and we thank the referees for helpful suggestions. Electronic supplementary material Additional file 1: STRUCTURE analysis of Malaysian and global isolates. The data provided represent the population structure of global isolates and the distribution of Malaysian isolates. (PDF 372 KB) References 1. Covacci A, Telford JL, Giudice GD, Parsonnet J, Rappuoli R:PFT�� solubility dmso Helicobacter pylori virulence and genetic geography. Science 1999, 284:1328–1333.CrossRefPubMed Carbohydrate 2. Linz B, Balloux F, Moodley Y, Manica A, Liu H, Roumagnac P, Falush D, Stamer

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