DNA-REPAIR PROFICIENCY - A POTENTIAL MARKER FOR IDENTIFICATION OF HIGH-RISK MEMBERS IN BREAST-CANCER FAMILIES

Breast cancer is the single largest cancer and causes the high rate of cancer mortality among women. A positive family history of breast can cer is recognized as one of the major risk factors for this disease. T he present study evaluates bleomycin (BLM)-induced chromosome sensitiv ity analysis in breast cancer families which provides indirectly a mea sure of the DNA repair defect of each person. BLM sensitivity assay on cultured lymphocytes of 36 familial breast cancer patients, their 85 first or second degree female relatives, 36 sporadic breast cancer pat ients and 40 age-and sex-matched controls (without any family history of cancer) were carried out to measure interindividual variation in th eir DNA repair capacity through mutagen-induced chromosome sensitivity analysis. Fifty percent of familial breast cancer patients and seven unaffected relatives showed hypersensitivity. Compared to hyposensitiv e relatives these seven subjects may be considered as high risk indivi duals. (C) 1998 Elsevier Science Ireland Ltd.