TABLE 3.

Numbers and types of polymorphisms observed in the 45 seventh pandemic isolates

Pair no.PrimersaNo. of fragmentsD
TotalConstantcPolymorphicInformative
1A/C74641040.680
2T/C6861740.375
3G/C6660610.609
4C/C4943630.660
5A/A7773410.522
6T/A56461030.802
7G/A5853540.730
8C/A5755220.226
9A/T8476820.603
10T/T5547830.725
11G/T5647930.837
12C/T73621160.559
13A/G6657950.591
14T/G48341460.663
15G/G6758920.649
16C/G4238410.189
Total996874122500.993
• a EcoRI-MseI +1/+1, denoting EcoRI and MseI primers, each with one selective base. The letters (such as A/C, for example) indicate selective bases (A and C, respectively, for example) for EcoRI and MseI.

• b Bands scored excluding some small and large fragments at the ends of the gel.

• c Constant fragmenSts refer to fragments present in all isolates. (See text for definition of polymorphic and informative fragments.)