The breakpoints of spontaneous chromosome aberrations in lymphocytes from patients with non-Hodgkin's lymphoma are nonrandomly distributed.

Abstract

The distribution of breakpoints in spontaneous chromosome aberrations (chromatid and chromosome gaps, breaks, and exchanges) was studied in lymphocytes from 30 untreated patients with non-Hodgkin's lymphoma (NHL) and 28 controls. A total of 102 breakpoints in the NHL group and 105 in the control group could be localized to specific chromosome bands. The breakpoint distribution was nonrandom among the NHL patients (P 0.10). The following bands appeared to be preferentially involved: lp22,2q33,4q27,5q31, and 9ql1 in the NHL group, and 2q21, 6q23,7q22, and 14q24 among controls. When comparing these hot spots with literature data on the distribution of breakpoints in the characteristic cytogenetic anomalies of NHL tumor cells, only two of them, 2q33 in the NHL group and 14q24 in the control group, coincided with bands involved in primary NHL-associated chromosome abnormalities. This suggests that the bands regularly affected in lymphoma cells are not constitutionally prone to breakage. None of the 9 hot spots detected in the NHL and control groups corresponded to known rare fragile sites. Six of them were located in bands containing aphidicolin inducible common fragile sites.