Detection of Helicobacter pylori (H.pylori) DNA in digestive systems from cadavers by real-time PCR

It is thought that there is a close relationship between regionality and DNA polymorphism of H.pylori. The application of H.pylori DNA to estimate the origin of unidentified cadavers may be possible. Previously, we detected H.pylori DNA in five stomach lesions by PCR in 50% of 100 cadavers in forensic autopsies. Furthermore, to see the localization of H.pylori in the digestive system, we tried to assay H.pylori DNA by real-time PCR. Mucous membranes at 14 points of digestive systems (5 points of the stomach, 1 point of the duodenum, 5 points of the small intestine, 3 points of the large intestine) were obtained from three cadavers whose stools were H.pylori-positive by an ImmunoCardST!HpSA detection kit. Genomic DNA was extracted using a DNA extraction kit. The 23Sr-DNA region was PCR-amplified (320bp) by a TOYOBO Kit and the same region was assayed by real-time PCR using a Taqman probe. The PCR products were detected in 5 points of the stomach and 1 point of the duodenum in each sample. The more peripheral the intestine lesion was the weaker the band became. The quantitative PCR showed that there were more PCR products in 5 points of the stomach and 1 point of the duodenum than in the other tissues. H.pylori DNA was detected not only in the stomach but also in the duodenum and small intestine. There was a difference in the amount of H.pylori DNA detected in each organ. Further study is required for immunohistochemical staining, and to determine the relationship between a persons natural state and the H.pylori DNA polymorphism (which codes for CagA).