not on the metacercariae. its ability to cause cancer is worsened by the discovery that its infection is often associated with those of helicobacter species (including h. pylori, which is primarily associated with ulcers, but also may cause stomach cancers). genetics o. viverrini has 12 (six pairs) of chromosomes, i.e. 2n = 12. the draft genome and transcriptomes were published in 2014. its genome is 634.5 mb in size. the species has 16,379 protein-coding genes.