Listeriosis is caused by the ingestion of pathogenic Listeria monocytogenes in contaminated food. In the October 26 Science, Glaser et al. report a comparative analysis of Listeria genomes aimed at identifying virulence genes (Science 2001, 294:849-852).They sequenced the genomes of two Listeria strains; pathogenic L. monocytogenes EGD-e and a non-virulent species L. innocua.L. monocytogenes contains a single circular chromosome of 2.9 Mb, while L. innocua has a 3 Mb chromosome and an 80 kb plas

There are about 16 million cases of typhoid fever throughout the world each year. In the October 25 Nature, Parkhill et al. report the complete genome sequence of the pathogenic culprit, Salmonella enterica serovar Typhi CT18 (Nature 2001, 413:848-852). The drug-resistant strain has a genome of 4.8 Mb containing over two hundred pseudogenes, some of which correspond to virulence genes in Salmonella typhimurium.In the same issue of Nature, McClelland et al. report the sequence of the Salmonella e

It is believed that the evangelist Luke was born in Antioch in Syria and died in Thebes, Greece, around 150 C.E (AD). His body was transported to Constantinople (Turkey) in 338 C.E. and later transfered to Padua, Italy. In the Early Edition of the Proceedings of the National Academy of Sciences, Cristiano Vernesi and colleagues at the University of Ferrara, Italy, describe experiments to verify the origins of the Padua body (doi/10.1073/pnas.211540498).They followed strict guidelines to isolate

In the Advanced Online Publication of Nature Genetics, John Ioannidis and colleagues at the University of Ioannina School of Medicine, Ioannina, Greece, describe a study to determine the reliability of disease association and genetic linkage reports (DOI:10.1038/ng749).They assembled data from published reports of 36 different disease associations, ranging from schizophrenia to hypertension. They used meta-analysis to explore the diversity and discrepancies between different studies. In 39% of c

The systematic deletion of all yeast ORFs, the Saccharomyces Genome Deletion Project, provides a powerful resource for large-scale 'parallel deletion analysis'. In the October 23 Proceedings of the National Academy of Sciences, Geoff Birrell and colleagues at Stanford University School of Medicine describe a screen for sensitivity to a genome-damaging agent (Proc Natl Acad Sci USA 2001, 98:12608-12613).They screened pools of 4,627 deletion strains for killing by ultraviolet (UV) irradiation and

Studies of the response to microbial infection in Drosophila have taught us much about the conserved features of the innate immune response. In the October 23 Proceedings of the National Academy of Sciences, Ennio De Gregorio and colleagues at the CNRS Centre de Genetique Moleculaire, Gif-sur-Yvette, France, describe a genome-wide analysis of the Drosophila immune response (Proc Natl Acad Sci USA 2001, 98:12590-12595).They used high-density oligonucleotide microarrays to probe over 13,000 genes

Domestication and cultivation have resulted in the generation of wild-looking forms of Mediterranean fruit crops derived from cultivated plants (cultivars). In the October 18 Nature, Roselyne Lumaret and Noureddine Ouazzani describe a genetic hunt for genuinely wild olives in forests of the Mediterranean (Nature 2001, 413:700).They collected samples from ten forests (40 trees per forest) in seven countries around the Mediterranean basin, scored them for allozyme markers, and compared them with t

Mutation of the Drosphila gene abnormal oocyte (abo), causes a recessive maternal-effect lethality, which can be rescued by specific regions of heterochromatin. In the October 9 Proceedings of the National Academy of Sciences, Maria Berloco and colleagues report a characterization of the abo protein product and its function (Proc Natl Acad Sci USA 2001, 98:12126-12131).Berloco et al. cloned the abo gene and showed that it encodes a chromosomal protein that binds specifically to the regulatory re

Metastasis poses the greatest threat to the survival of cancer patients, yet the molecular events underlying this complex process are unclear. In the October 11 ScienceXpress, Saurabh Saha and colleagues at the Johns Hopkins Medical Institutions, Baltimore, USA, describe serial analysis of gene expression (SAGE) to identify genes involved in liver metastasis in colorectal cancer patients (ScienceXpress 10.1126/science.1065817).They developed an immunoaffinity fractionation procedure to purify co

During T-lymphocyte activation, signals from a number of cell-surface receptors must be integrated to ensure the appropriate genetic response. Non-dividing, primary T lymphocytes are notoriously difficult to transfect, presenting an experimental limitation to dissecting signaling mechanisms. In the October issue of Nature Medicine, Michael Bell and colleaguess from the Mayo Clinic in Rochester, Minnesota, describe an efficient method for introducing DNA into non-dividing lymphocytes, so as to an

Chromatin fibers adopt higher-order structures that define chromosomal regions with distinct functional properties. In the October 9 Proceedings of the National Academy of Sciences, Nick Gilbert and James Allan, from the University of Edinburgh in Scotland, UK, describe the use of analytical sucrose gradient sedimentation to examine chromatin fibres released from centromeric heterochromatin (Proc Natl Acad Sci USA 2001, 98:11949-11954).They studied soluble chromatin released from murine NIH3T3 f

Now that we have the whole human genome sequence, the challenge remains to identify all the genes and transcripts hidden within it. In the October 9 Proceedings of the National Academy of Sciences, Anamaria Camargo and colleagues, from the Ludwig Institute for Cancer Research in Sao Paolo, Brazil, report the results from a Brazilian project aimed at defining the human transcriptome (Proc Natl Acad Sci USA 2001, 98:12103-12108).The approach being used exploits open reading frame expressed sequenc