To see an interphase chromosome or: How a disease can be associated with specific nuclear genome organization

The last hierarchical level of cellular genome organization is the spatial arrangement of chromosomes within the nuclear space. Despite of high regulatory potential and functional implications, issues concerning nuclear organization at chromosomal level are rarely addressed because of limitations in visualizing interphase chromosomes. The problem is especially seen when an attempt to associate specific patterns of nuclear genome organization with a pathological condition is made. Fortunately, advances in molecular cytogenetics have provided for a solution to visualize chromosomes in interphase nuclei at molecular resolution. A study in this issue of BioDiscovery shows the way of how to identify interphase chromosome architecture at molecular resolutions and demonstrates the involvement of specific nuclear genome organization in generating a cancercausing chromosomal aberration (translocation between chromosomes 8 and 21 in acute myelogenous leukemia). Authors’ findings suggest interphase molecular cytogenetic techniques (i.e. interphase chromosome-specific multicolor banding or ICS-MCB) to be required to perform studies regarding nuclear genome organization at chromosomal level and its role in disease pathogenesis.