Cytogenetic sensitivity of G0 lymphocytes of Fanconi anemia patients and obligate carriers to mitomycin C and ionizing radiation

It is well known that Fanconi anemia (FA) patients show a hypersensitivity to the effect of cross-linking agents such as mitomycin C (MMC) and diepoxybutane (DEB), while the sensitivity of these patients to ionizing radiation is still controversial. Fanconi anemia heterozygotes do not show a hypersensitivity to the above mentioned agents compared to normal individuals. To examine the radio-sensitivity of Fanconi anemia patients and heterozygotes, ten patients and 13 heterozygotes were enrolled in this study. Standard metaphase analysis for detection and verification of radio-sensitivity was used to establish the relationship between gamma-ray and chromosome breakages in these groups. Statistical analysis was used for the assessment of aberrations including chromatid and chromosome breaks and exchanges. Results of chromosome aberration yield that: (i) differentiation between obligate carriers and the control group after MMC treatment and gamma irradiation was not possible; (ii) homozygotes were clearly distinguishable from heterozygotes and controls after MMC treatment; (iii) FA patients don't show hypersensitivity to gamma irradiation compared to normal controls and heterozygous carriers.