Red squirrels (Sciurus vulgaris) thrive in the north of England and Scotland and occupy a patchwork of highly fragmented woodland habitats. In the September 21 Science, Marie Hale and colleagues from the University of Newcastle, UK, report a genetic investigation of the impact of habitat fragmentation on British red squirrel populations (Science 2001, 293:2246-2248).They assembled over 100 squirrel samples collected between 1918 and 2000 and analysed four polymorphic microsatellite loci for each

Identifying the population origins of individual fish is important in assisting the policing of fishing waters and the tracking down of poachers. In the September 20 Nature, Einar Nielsen and colleagues from the Danish Institute for Fisheries Research describe a simple approach using microsatellite markers to assign individual Atlantic cod fish (Gadas morhua) to their original population (Nature 2001, 413:272).They studied three cod populations; from the North Sea, the Baltic Sea, and the northe

Although many gene-inactivation technologies have been applied to bacterial genetics, the potential for using antisense technology has not been extensively explored. In the September 21 Science, Yindo Ji and colleagues from GlaxoSmithKline Pharmaceuticals in Collegeville, Pennsylvania, describe a comprehensive genomic analysis of the human pathogen Staphylococcus aureus using a regulated antisense strategy (Science 2001, 293:2266-2269).They used an adapted tetracycline-dependent (tet) regulatory

Gene therapy with a mini-agrin transgene rescues muscular dystrophy in mice lacking a functional lama2 gene.

One of the challenges for microarray analysis is making sense of the mountains of data that this technology can generate. In the September 14 Science, Stuart Kim and colleagues from Stanford University show how three-dimensional maps can be used to navigate microarray data (Science 2001, 293:2087-2092).They established a compendium of gene expression profiles for the Caenorhabditis elegans genome using data from 553 microarray experiments. They created topological maps in which distance defines

If clinicians could predict how a cancer patient would respond to specific chemotherapeutic drugs, they would be able to choose an individualized treatment protocol with greater chances of success and minimized side effects. In the September 11 Proceedings of the National Academy of Sciences, Jane Staunton and colleagues from the Whitehead Institute, Cambridge, Massachusetts describe a genomic approach for predicting chemosensitivity (Proc Natl Acad Sci USA 2001, 98:10787-10792).They measured th

Early analysis of the Caenorhabditis elegans genome failed to detect a gene resembling the important mammalian tumour suppressor gene p53. In the September 13 ScienceXpress, Brent Derry and colleagues at the University of California at Santa Barbara report that there is a nematode p53 orthologue that is involved in apoptosis and the stress response (zdoi;10.1126/science.1065486).They named the gene cep-1 (C. elegans p53-like 1). Disrupting cep-1 expression (by mutation or RNAi experiments) had n

Breast carcinomas can be classified into different subclasses using microarray profiling.

In the September 11 Proceedings of the National Academy of Sciences, Shelley Cao and colleagues from the University of California, Riverside, report the use of microarray analysis to investigate gene profiles associated with aging (Proc Natl Acad Sci USA 2001, 98:10630-10635).They compared the expression of 11,000 genes in mRNA samples from the livers of young (7 months) and old (27 months) mice. The expression of 20 known genes increased with age and 26 decreased; these included genes associate

Medulloblastoma is the most common malignant brain cancer in children. In the Advanced Online Publication of Nature Genetics, Tobey MacDonald and colleagues from the Children's National Medical Center, Washington, DC, report the use of oligonucleotide expression profiling (Affymetrix G110 cancer arrays) to define a set of genes that are prognostic for medulloblastoma metastasis (DOI:10.1038/ng731).They analysed 23 primary medulloblastomas that were either metastatic (M+) or non-metastatic (M0) a

The Spanish influenza virus pandemic of 1918 killed more than 20 million people worldwide. In September 7 Science, Mark Gibbs and colleagues from the Australian National University in Canberra propose that the pandemic was the result of a recombination between swine-lineage and human-lineage viral strains (Science 2001, 293:1842-1845).They analysed sequences of the hemagglutinin (HA) gene from 30 H1-subtype influenza isolates, using the sister-scanning method and a maximum likelihood method. The

The CDKN2A (INK4a/ARF) locus encodes two distinct cell cycle inhibitors, p16Ink4a and p19ARF, both of which have been implicated in tumorigenesis. In the September 6 Nature, two independent groups report the generation of knockout mice specifically lacking p16Ink4a. Surprisingly, mouse embryonic fibroblasts (MEFs) lacking p16Ink4a were normal in terms of growth characteristics, senescence phenotypes and resistance to oncogenic Ras-induced transformation.These observations are in contrast to resu