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It is often necessary in population biology to compare two sets of distance measures. These measures can be based on genetic markers, morphological traits, geographic separation, ecological divergence, and so on. The distance measures can take various forms and frequently have unknown distributional properties. Many different procedures have been developed to compare the correspondence of one set of distances with another set. Prominent among them are the: (1) matrix correlation techniques of Sokal and Rohlf (1962), and Sneath and Sokal (1973); (2) networkmatching techniques of Spielman (1973); (3) matrix dilation and rotation techniques of Gower (1971) and of Schonemann and Carrol (1970); and (4) smallest-space techniques of Lingoes (1965) and Guttman (1968). Each of these strategies has strong points, but all suffer from a difficulty in assessing the statistical significance of attained correspondence. The problem is that a set of all possible pairwise distances between k units (populations, taxa, habitats, etc.) cannot be independent. More recently, a test of matrix correspondence-originally developed by Mantel (1967) and widely applied in geography (Hubert and Golledge, 1982) and psychometrics (Hubert, 1979a, b)-has caught the attention of population biolo

Sites of transcription of polyadenylated and nonpolyadenylated RNAs for 10 human chromosomes were mapped at 5-base pair resolution in eight cell lines. Unannotated, nonpolyadenylated transcripts comprise the major proportion of the transcriptional output of the human genome. Of all transcribed sequences, 19.4, 43.7, and 36.9% were observed to be polyadenylated, nonpolyadenylated, and bimorphic, respectively. Half of all transcribed sequences are found only in the nucleus and for the most part are unannotated. Overall, the transcribed portions of the human genome are predominantly composed of interlaced networks of both poly A+ and poly A- annotated transcripts and unannotated transcripts of unknown function. This organization has important implications for interpreting genotype-phenotype associations, regulation of gene expression, and the definition of a gene.

The Encyclopedia of DNA Elements (ENCODE), http://encodeproject.org, has completed its fifth year of scientific collaboration to create a comprehensive catalog of functional elements in the human genome, and its third year of investigations in the mouse genome. Since the last report in this journal, the ENCODE human data repertoire has grown by 898 new experiments (totaling 2886), accompanied by a major integrative analysis. In the mouse genome, results from 404 new experiments became available this year, increasing the total to 583, collected during the course of the project. The University of California, Santa Cruz, makes this data available on the public Genome Browser http://genome.ucsc.edu for visual browsing and data mining. Download of raw and processed data files are all supported. The ENCODE portal provides specialized tools and information about the ENCODE data sets.