Study of the mosquito genome is driven by the need for improved strategies to control the transmission of malaria and other mosquito-borne diseases. In the February 13 Proceedings of the National Academy of Science, Tu describes the use of a novel computer program, FINDMITE, to search systematically for DNA transposable elements in the genome of the African malaria mosquito Anopheles gambiae (Proc Natl Acad Sci USA 2001, 98:1699-1704). The program identified eight novel families of miniature inv

Experiments with irradiated mice show that damage to DNA in the paternal genome is hazardous for the maternally derived genome.

In the February 16 Science, Venter et al. announce the sequencing of the euchromatic portion of the human genome by a whole-genome shotgun sequencing approach (Science 2001, 291:1304-1350). The sequencing achievement was accomplished by Celera Genomics in nine months in a factory-scale project involving 300 automatic squencing machines (ABI PRISM 3700) producing 175,000 sequence-reads per day. The company generated 14.8 gigabases (Gb) of DNA sequence and combined data with the public GenBank) da

In the February 15 Nature, the International Human Genome Sequencing Consortium announces the completion of the first draft of the sequence of the human genome. The publication is the achievement of the decade-long Human Genome Project based on open international collaboration (involving 20 groups) and rapid, unrestricted data release (via GenBank). The draft sequence covers 94% of the genome, which is estimated to be about 3.2 Gigabases (Gb), 25 times the size of any previously sequenced genome

Telomere length shortens upon culture of fibroblast cells in vitro. But what happens to chromosomal ends and telomerase activity when nuclei from these aged cells are used to clone animals by somatic nuclear transfer? In the January 30 Proceedings of the National Academy of Science Betts et al. report on telomeres and telomerase activity in early and late-passage donor fibroblasts and recipient cloned bovine embryos (Proc Natl Acad Sci USA 2001, 98:1077-1082). Despite the reduction in telomere l

The human intestine is home to numerous populations of microorganisms, but we know little about how the gut microflora influence our physiology. As described in the February 2 Science, Hooper et al. took a genomics approach to investigate the affect of resident bacteria on host gene expression in the gut (Science 2001, 291:881-884). The authors infected germ-free mice with the common gut bacterium Bacteroides thetaiotaomicron and measured host transcriptional responses using microarray analysis.

The ends of vertebrate chromosomes are protected by telomeric structures containing several kilobases of short repeated sequences (TTAGGG). In the January Molecular and Cellular Biology Kilburn et al. describe their investigation of the effect of telomeric repeats inserted at defined intrachromosomal locations (Mol Cell Biol 2001, 21:126-135). They used site-specific recombination to place an 800 nucleotide fragment from a functional vertebrate telomere repeat, in either orientation, within a sp

The lack of molecular markers is a major factor contributing to the poor diagnosis and survival of women suffering from epithelial ovarian cancer. As reported in the January 30 Proceedings of the National Academy of Science, Welsh et al. identified groups of genes whose expression correlated with clinical observations and therefore might be useful diagnostic markers for ovarian cancer (Proc Natl Acad Sci USA 2001, 98:1176-1181). They developed a high-throughput protocol (which they have termed '

In the January 25 Nature, Iyer et al. describe an elegant technique to identify transcriptional target genes throughout the genome (Nature 2001, 409:533-538). They combined chromatin immunoprecipitation (ChIP) with microarray analysis (DNA chips) to probe individual protein-genome interactions. The technique involved cross-linking, immunoprecipitation, PCR amplification and fluorescent labeling, followed by hybridization to microarrarys containing genomic DNA. They searched the yeast genome fo

Chromatin silencing depends on passage through the S-phase of the cell cycle and was widely believed to depend on DNA replication. In two papers in the January 26 Science, Kirchmaier and Rine and Li et al. challenge this dogma by reporting that the establishment of transcriptional silencing can occur in the absence of replication (Science 2001, 291:646-650; Science 2001, 291:650-653). Both groups used an ingenious genetic trick, involving site-specific recombination, to generate non-replicating

Genomic imprinting is characterized by epigenetic regulation of mRNA expression from a single parental allele. The two parental alleles of imprinted genes are differentially methylated. The mouse gene Peg3 is imprinted and has been shown to control the maternal nurturing of newborn pups in mice. In the January Genomics, Murphy et al. show that the human homolog of Peg3 is also imprinted (Genomics 2001, 71:110-117). They identified a CpG island (CpG islands are much more frequent around imprinted

O157:H7 is the unassuming name of a deadly strain of Escherichia coli that has been killing thousands of people every year, ever since the first outbreak was caused by contaminated hamburgers in 1982. In the January 25 Nature Perna et al. describe the sequencing of the entire genome of this killer bug in search of clues to its pathogenesis (Nature 2001, 409:529-533). Comparison with the genome of non-pathogenic laboratory E. coli strain K-12 revealed 1,387 new genes, which are organized into dis