This article examines methods, issues and controversies that have
arisen over the last decade in the effort to organize sequences of DNA base
information into homogeneous segments. An array of different models and
techniques have been considered and applied. We demonstrate that most
approaches can be embedded into a suitable version of the multiple change-point
problem, and we review the various methods in this light. We also propose and
discuss a promising local segmentation method, namely, the application of split
local polynomial fitting. The genome of bacteriophage $\lambda$ serves as an
example sequence throughout the paper.