Table 2 The similar pattern of codon usage in the target regions in both US and EU serotypes

ORF1a

the 2^nd to 4^th, 6^th to 8^th, 10^th, 11^th, 14^th, 15^th, 17^th, 20^th to 24^th, 26^th, 29^th to 36^th, 39^th, 44^th, 45^th, 48^th

ORF2

the 3^rd to 5^th, 14^th, 17^th, 21^st, 23^rd, 24^th, 28^th, 31^st, 34^th, 36^th, 37^th, 41^st, 44^th, 46^th, 49^th, 50^th

ORF3

the 2^nd, 6^th, 9^th to 15^th, 18^th to 20^th, 23^rd to 26^th, 28^th to 31^st, 33^rd to 36^th, 38^th, 39^th, 41^st, 44^th, 45^th, 47^th to 49^th

ORF4

the 2^nd to 10^th, 12^th, 13^th, 15^th to 18^th, 20^th, 22^nd to 25^th, 27^th to 29^th, 33^rd, 34^th, 36^th, 37^th, 39^th, 40^th, 43^rd, 45^th, 46^th, 47^th to 50^th

ORF5

the 7^th, 11^th, 13^th, 15^th to 17^th, 20^th, 21^st, 25^th to 31^st, 33^rd, 37^th, 39^th, 41^st, 50^th

ORF6

the 11^th, 17^th, 18^th, 20^th, 23^rd, 25^th, 33^rd, 38^th, 41^st, 43^rd, 44^th, 49^th

ORF7

the 2^nd, 5^th, 6^th, 8^th, 9^th, 15^th, 18^th, 21^st to 23^rd, 26^th to 31^st, 36^th, 38^th to 40^th, 46^th