Distributions of numerical abnormalities and structural breakpoints. (A) Loss of chromosomes 14 (n = 44), 13 (n = 25), and Y (n = 23), and gain of chromosome 3 (n = 31), are common; the median number of these abnormalities is 0 (range, 0-17). (B) Structural breakpoints at 6q (n = 58), 9q (n = 52), 1q (n = 50), 3q (n = 50), 2q (n = 42), and 14q (n = 42) are common; the median number of structural breakpoints is 3 (range, 0-22).