technical focur Human chromosome analysis by machine

It is almost a quarter of a cen- tun/since the earliest reported attempts to use a computer to analyse human chromosomes x. While the effort oftheinterven- ing years has been successful to the extent that a number of manufacturers now pro- duce machines that assist cyto- genetic analysis z, there are also some notable gaps in the capabilities of these machines. In this review of the application of image analysis techniques to automating chromosome analy- sis, we shall not attempt to review the performance of particular machines, but instead try to explain more generally why some tasks have been successfully automated, while others that may appear equally simple to the cytogeneticist have proved elusive. The techniques of image processing and analysis are conceptually simple. Animage, for example of a field of a microscope slide, is captured in digital form by measuring the light intensity at each of a regular array of points, known as picture elements or pixels. The digital image may then