G-banded karyotype and ideogram for the North Atlantic right whale (Eubalaena glacialis).

Published cytogenetic data for extant cetacean species remain incomplete. In a review of the literature, we found karyotypic information for 6 of the 13 tentatively recognized species of the suborder Mysticeti (baleen whales). Among those yet to be described is the critically endangered North Atlantic right whale (Eubalaena glacialis).

Locus control region elements HS2 and HS3 in combination with chromatin boundaries confer high-level expression of a human beta-globin transgene in a centromeric region.

Expression constructs are subject to position-effects in transgenic assays unless they harbour elements that protect them from negative or positive influences exerted by chromatin at the site of integration. Locus control regions (LCRs) and boundary elements are able to protect from position effects by preventing heterochromatization of linked genes. The LCR in the human beta-globin gene locus is located far upstream of the genes and composed of several erythroid specific DNase I hypersensitive (HS) sites.

Translocation (X;20)(q13.1;q13.3) as a primary chromosomal finding in two patients with myelocytic disorders.

Reports of X chromosome translocations, as primary chromosomal changes associated with hematologic disorders, remain relatively uncommon. Herein, we report the detection, by conventional cytogenetic methods, of a cytogenetically identical t(X;20) in two different patients with hematologic disorders (probable myelodysplasia and polycythemia vera/acute myelocytic leukemia). In both cases, this translocation appeared as the primary clonal chromosome abnormality, with breakpoints occurring in the long arms of both the X chromosome and chromosome 20 (Xq13.