genes involved in complex behavior.

The use of calibrated reference samples should help with the interpretation and comparison of microarray data.

Lentiviruses can be used to deliver genes to the testes and rescue infertility in sterile mice.

Analysis of the human genome sequence provides evidence for extensive duplication events during vertebrate evolution.

Genomic sequence analysis identifies pathogenicity proteins secreted into host cells by a plant pathogen.

X-chromosome inactivation, the largest epigenetic event known, involves random silencing of one of the two X chromosomes in the cells of female mammals. In an Advanced Early Publication in Nature Genetics, Fei Xue and colleagues report defects in X inactivation in cells from cloned bovine embryos (NatGenet 2002, DOI:10.1038/ng900).Xue etal. looked at the allele-specific expression of the X-linked monoamine oxidase type A (MAOA) gene and at the expression of Xist and other X-linked genes in clone

Post-translational regulation of p53 regulates its activity and tumor suppressor functions. In an Advanced Online Publication in Nature Genetics, Dmitry Bulavin and colleagues from the National Institutes of Health describe how oncogenic Ras regulates p53 phosphorylation (Nat Genet 2002, DOI:10.1038/ng894).Bulavin et al. used antibodies specific for different modified forms of p53 and showed that oncogenic Ras induced p53, accumulation and phosphorylation of two specific serine residues that are

Advances in medicine will undoubtedly be linked to our ability to correlate human genetic variation with disease. In the 23 May ScienceXpress, Stacey Gabriel and colleagues report a large-scale analysis of haplotypes in the human genome (Sciencexpress 2002, DOI:10.1126/science.1069424).Gabriel et al. characterized haplotype patterns for 51 genomic regions with an average size of 250 kb (covering 13 megabases) from African, European and Asian DNA samples. They genotyped thousands of single nucleo

Malaria kills up to 2.7 million people a year and the death toll is predicted to double in the next two decades. In the 23 May Nature, Junitsu Ito and colleagues describe a transgenic strategy to halt malaria by regulating transmission by mosquitoes of the Plasmodium parasites that cause the disease(Nature 2002, 417:452-455).Ito et al. used the carboxypeptidase (CP) promoter that is activated by a blood meal, and CP signal sequences that direct protein secretion into the midgut lumen, to drive e

A clear example of cell-type-specific gene regulation by cytosine methylation has been described in epithelial cells.

Genetic analysis of medaka fish has identified a gene on the Y chromosome that is required for male development.

RNA silencing processes result in the sequence-specific degradation of RNA and effective post-transcriptional gene silencing. In the May 17 Science, Hongwei Li and colleagues from the University of California, Riverside report that Flock House Virus (FHV) is both an initiator and a target of RNA silencing (Science 2002, 296:1319-1321).Li et al. observed that B2 gene of FHV resembles a plant virus gene encoding a silencing suppressor. Expression of the FHV B2 protein in plants prevented RNA silen