FIG. 3.

IS6110 RFLP patterns of different mixtures of the DNAs of two SCCs of an M. tuberculosis strain differing in a single IS6110 element. Lane 1 shows the pattern of pure DNA of one SCC. Lanes 2 to 21 depict patterns of mixtures of this DNA with an increasing amount of DNA of another SCC containing an additional IS6110 copy at a PvuII restriction fragment of approximately 3.5 kb. The numbers in the second horizontal row indicate the ratios of the DNA mixtures. The numbers on the left indicate the sizes of standard DNA fragments in kilobase pairs.