Fanconi's anemia is an autosomal recessive disorder with manifestation of chromosomal instability inducible by alkylating agents. Since 1989 we studied 85 patients with suspected Fanconi's anemia (FA) to confirm diagnosis. Cytogenetic analyses were performed on spontaneous and induced cultures of peripheral blood samples. Induction was carried with mitomycin-C (MMC) or diepoxybutane (DEB). The normal range of spontaneous, MMC and DEB-induced breaks were 0.00-0.10, 0.00-0.16 and 0.00-0.16 per cell respectively. Fanconi's anemia was confirmed when breaks were above the normal threshold. According to this criterion 59 patients were confirmed as having FA. Some of the siblings were also investigated to exclude disease especially when donors for bone marrow transplantation are sought. Among 28 studied siblings, we found 6 affected. Therefore, 65 cases were diagnosed as FA according to cytogenetics criteria. In 13 out of the 65 patients (20%) instability was detected only after induction.

Fanconi's anemia is an autosomal recessive disorder with manifestation of chromosomal instability inducible by alkylating agents. Since 1989 we studied 85 patients with suspected Fanconi's anemia (FA) to confirm diagnosis. Cytogenetic analyses were performed on spontaneous and induced cultures of peripheral blood samples. Induction was carried with mitomycin-C (MMC) or diepoxybutane (DEB). The normal range of spontaneous, MMC and DEB-induced breaks were 0.00-0.10, 0.00-0.16 and 0.00-0.16 per cell respectively. Fanconi's anemia was confirmed when breaks were above the normal threshold. According to this criterion 59 patients were confirmed as having FA. Some of the siblings were also investigated to exclude disease especially when donors for bone marrow transplantation are sought. Among 28 studied siblings, we found 6 affected. Therefore, 65 cases were diagnosed as FA according to cytogenetics criteria. In 13 out of the 65 patients (20%) instability was detected only after induction.