... segmentedaccording to the turning points in the z¢ curves, mostof these regions are identified to be isochores. In addi-tion, in [17], it is observed that there are still large fluc-tuations in the detected ... regions are approximately straight lines,indicating the GC content is nearly constant in theseregions, which are considered to be isochores [2].Through the intuitive z¢ curves, the two remainingquestions ... describe the real structures.Most of the regions have large fluctuations, indicating the GC content is inhomogeneous in these regions.Therefore, they are called ‘isochore-like regions’ in thispaper....