ABSTRACT
The Ebstein-Barr virus has been suggested as a possible pathogenetic factor29 in the X-linked lymphoproliferative syndrome. Of particular interest are the fragile chromosomal syndromes, where fragile sites associated with breakage and repair of chromosomal defects are transmitted through families. A high percentage of the inheritable and constitutive fragile sites have been mapped to genetic sites associated with human cancer.30 These chromosomal rearrangements have been associated with malignancy in at least six out of the 16 inheritable fragile chromosome sites and has also been identified in other non-inherited fragile chromosome sites.30 As a result of the chromosome fragility in these cases, deletions and chromosomal fragments may occur. Should the fragile sites break close to a proto-oncogene location, the activation of the oncogene may result in the malignant transformation of the cells. In several disorders in sexual differentiation, the incidence of gonadal tumors has been increased.
