Centromeric heterochromatin instability of chromosomes 1, 9, and 16 in variable immunodeficiency syndrome--a virus-induced phenomenon?

Centromeric instability of chromosomes 1, 9, and 16 has been described in eight patients with variable immunodeficiency. Although the pathogenetic relationship of these cytogenetic abnormalities with the clinical symptoms are unclear, it has nevertheless been proposed that they are a hallmark of this syndrome. Based on the clinical, immunological and cytogenetic data from the literature, a model is presented suggesting that the cytogenetic changes are not causatively involved in the immunodeficiency syndrome, but result from specific virus infections occurring as a consequence of the immunodeficiency in genetically predisposed individuals.