REPRODUCTIVE OUTCOME IN 3 FAMILIES WITH A SATELLITED CHROMOSOME-4 WITH REVIEW OF THE LITERATURE

We describe 3 families segregating for a translocation of the nucleolu s organizer region (NOR) onto chromosome 4. Review of previously repor ted cases of translocations involving NOR and chromosome 4 shows that these translocations may be associated with variable reproductive outc omes. We provide evidence that imprinting is not the mechanism respons ible for the variable reproductive outcomes in the case of satellited 4p chromosomes; this may offer indirect support for a ribosomal gene p osition effect. Translocated ribosomal genes may influence the express ion of neighboring genes and could explain the variable phenotypes in individuals with satellited nonacrocentric chromosomes. We recommend t hat prenatal counseling of individuals with satellited nonacrocentric chromosomes should be cautious. (C) 1995 Wiley-Liss, Inc.