Chromosomal disorder and neoplastic diseases in a family with inherited fragile 16. Causality or casualty?

We describe a family with an inherited fragile chromosome 16 with the concurrence of a constitutional chromosome abnormality, together with neoplastic pathology within the family. The following findings should be pointed out: in relation to the constitutional chromosome pathology, of the proband's 3 children, the eldest daughter was a carrier of the fragile 16, the same as the father, and the second child, a son, had Down syndrome (trisomy 21). Regarding the tumoral pathology of this family, one of the proband's daughters died in childhood from acute lymphoblastic leukemia, whereas the proband developed two different malignant hematologic disorders: a follicular lymphoma and an acute nonlymphocytic leukemia (M5 type). Moreover, two independent acquired chromosome disorders coexisted in the proband; each of these was related to one of the respective hematologic disorders.