COMPOSITIONAL HETEROGENEITY WITHIN, AND UNIFORMITY BETWEEN, DNA-SEQUENCES OF YEAST CHROMOSOMES

The heterogeneity within, and similarities between, yeast chromosomes are studied. For the former, we show by the size distribution of domai ns, coding density, size distribution of open reading frames, spatial power spectra, and deviation from binomial distribution For C + G% in large moving windows that there is a strong deviation of the yeast seq uences from random sequences. For the latter, not only do we graphical ly illustrate the similarity for the above mentioned statistics, but w e also carry out a rigorous analysis of variance (ANOVA) test. The hyp othesis that all yeast chromosomes are similar cannot be rejected by t his test. We examine the two possible explanations of this interchromo somal uniformity: a common origin, such as genome-wide duplication (po lyploidization), and a concerted evolutionary process.