Table 2.

Mean synonymous (K_S) and non-synonymous (K_A) nucleotide substitution rates between pairs of sequences within three defined regions of vacA. Comparisons among five m1 alleles with full-length vacA sequence data,^a and between these five alleles and the one m2 allele with full-length sequence data^b

Comparison	Number of comparisons	5′ regionc			Mid regiond			3′ regione
		KS	KA	KA/KS	KS	KA	KA/KS	KS	KA	KA/KS
m1 vs m1	10	0.11	0.029	0.25	0.17	0.051	0.31	0.11	0.027	0.25
m1 vs m2	5	0.23	0.105	0.46	0.47	0.273	0.58	0.11	0.032	0.30

^aStrains and references for these five vacA alleles are 60190 [4]; 26695 [25]; 11638 [19]; 185-44 [23]; 43526 [15].

^bStrain Tx30a [1].

^cDefined as 1 to 1620 bp of published sequence of strain 60190 [4].

^dDefined as 1621 to 2571 bp of published sequence of strain 60190 [4].

^eDefined as 2572 to 3864 bp of published sequence of strain 60190 [4].