ABSTRACT
The nuclear genome is split into a set of linear DNA molecules, each contained in a chromosome. No exceptions to this pattern are known: all eukaryotes that have been studied have at least one chromosome and the DNA molecules are always linear. The variations in gene density that occur along the length of a eukaryotic chromosome mean that it is difficult to identify regions in which the organization of the genes can be looked on as ‘typical' of the genome as a whole. The genetic organization of the yeast genome is clearly much more compact than that of the human version. The genes themselves are much shorter, having fewer introns, and the spaces between the genes are relatively short, with much less space taken up by interspersed repeats and other noncoding sequences.
