Increased levels of spontaneous and mutagen-induced chromosome aberrations in skin fibroblasts from patients with adenomatosis of the colon and rectum.

Fibroblast cell strains were established from skin biopsies taken from patients with adenomatosis of the colon and rectum (ACR) and their relatives. A total of 57 different strains (33 from patients and 24 from healthy members of ACR families not at an increased risk for colon polyposis) were tested for their frequencies of spontaneous structural chromosome aberrations, i.e., chromatid and isochromatid gaps, breaks, and interchanges. In 47 strains (27 from patients, 20 from controls), the frequencies of structural chromosome aberrations were also determined after exposing the cells to N-methyl-N'-nitro-N-nitroso-guanidine (MNNG). Both spontaneously and after mutagen treatment, the group of patient strains exhibited, on average, approximately twice the number of chromosome aberrations found in the control group. This increase was highly significant (p less than 0.001), even though there was a considerable overlap between patient and control strains. Treatment with MNNG led to a marked increase in chromosome aberrations in both patients and controls. The small differences in aberration frequencies seen between Gardner and other patient strains were clearly insignificant.