High incidence of mutations in patients with a more than 2-fold rise in BCR-ABL in consecutive analyses. The graphs represent the BCR-ABL values before (open diamonds) and after the rise (shaded diamonds). ND = the level below which BCR-ABL was not detectable. (A) Patients with a mutation. In 31 of the 34 patients, the mutation was detectable at the time of the rise and within 3 months in the remaining 3 patients. The circled number above the 3 patients indicates the month after the rise that the mutation became detectable. (B) Patients without a mutation.