Observations of de novo clones of cytogentically aberrant cells in primary fibroblast cell strains from phenotypically normal women.

In a recent study of chromosome breakage frequencies in 36 primary fibroblast cell strains derived from skin from 10 phenotypically normal women, we observed seven different clones of cells having consistent chromosomal abnormalities. Five of the stem lines were noted in cultures from "control" women and two in fibroblasts from women taking oral contraceptives. We observed aneuploid clones as well as stem lines bearing structural abnormalities (e.g., translocation, inversions). The various aberrant clones were found in cultures ranging in age from 41 to 144 days and comprised varying percentages of the cell populations ranging from 0.8% to virtually 100%. The possible evolution in culture of clones of cells having aberrant karyotypes should be considered in interpreting findings from fibroblast cultures initiated for clinical evaluation.