cagA and vacA genotype of Helicobacter pylori associated with gastric diseases in Xi’an area

Table 1 Oligonucleotide primers used for vacA typing

Gene and region amplified	Genotype identified	Primer designation	Primer sequence	Size of PCR product(bp)
Mid-region	m1/m2	VAG-F	5’CAATCTGTCCAATCAAGCGAG3’	567/642
		VAG-R	5’GCGTCAAAATAATTCCAAGG3’
Signal sequence	s1/s2*	VA1-F	5’ATGGAAATACAACAAACACAC3’	259/286*
		VA1-R	5’CTGCTTGAATGCGCCAAAC3’
	s1a	SS1-F#	5’GTCAGCATCACACCGCAAC3’	190
	s1b	SS3-F#	5’AGCGCCATACCGCAAGAC3’	187

vacA types s1 and s2 were differentiated on the size of the PCR product. # Used with reverse primer VA1-R.