Table 3. Codon position-dependent patterns of nucleotide substitutions among the 102 Slovakian VDPV strains.

Codon position	Original nucleotide	Substitute nucleotide
		A	T	C	G
Total codon	A	-	1.72	1.94	17.47
	T	2.07	-	25.26	1.82
	C	2.07	22.38	-	1.82
	G	19.79	1.72	1.94	-
Position 1	A	-	2.42	2.15	15.06
	T	3.15	-	23.24	3.75
	C	3.15	26.15	-	3.75
	G	12.63	2.42	2.15	-
Position 2	A	-	3.41	4.63	20.4
	T	4.04	-	7.56	2.17
	C	4.04	5.57	-	2.17
	G	37.98	3.41	4.63	-
Position 3	A	-	1.35	1.5	17.91
	T	1.52	-	26.98	1.42
	C	1.52	24.31	-	1.42
	G	19.21	1.35	1.5	-

Each entry shows the probability of substitution (r) from one base (row) to another base (column) [49]. For simplicity, the sum of r values is made equal to 100. Rates of different transitional substitutions are shown in bold and those of transversional substitutions are shown in italics. Evolutionary analyses were conducted in MEGA5 [31].