Differences in gene expression levels might be sufficient to account for the behavioural and cognitive functions that distinguish us from monkeys. In the April 12 Science, Wolfgang Enard and colleagues address this issue by studying the transcriptome and proteome in human and chimpanzee tissues (Science 2002, 296:340-343).Enard et al. compared mRNA levels in the brains and livers of six humans, six chimps (Pan troglodytes) and two orangutans (Pongo pygmaeus) using oligonucleotide microarrays rep

Men are thought to have a higher mutation rate than women and the male-to-female mutation ratio (the 'alpha' value) in primates has been estimated at around 4-6. This estimation has recently been challenged, and it has been suggested that the alpha ratio may be as low as 1.7. In the April 11 Nature, Kateryna Makova and Wen-Hsiung Li provide evidence supporting the higher estimates (Nature 2002, 416:624-626).Makova & Li sequenced over 10 kilobases of genomic DNA from a non-coding region of th

Researchers have developed an optimized procedure for analyzing the genome and transcriptome of single tumour cells.

French scientists have succeeded in generating cloned rabbits by nuclear transfer.

Spotting modified DNA directly onto untreated glass surfaces offers an efficient system for identifying genomic abnormalities in tumor samples.

Two independent groups report draft sequences of the rice genome.

In an Advanced Online Publication from Nature Genetics, Klose at al. describe a comprehensive genetic study of proteins in the murine brain (Nat Genet 2002, DOI:10.1038/ng861).They took advantage of crosses from the European collaborative interspecific backcross (EUCIB) project, and prepared brain tissues from 200 backcross progeny (B1) animals. Klose at al. then analyzed the brain proteome using two-dimensional gel electrophoresis. Comparison of over 8000 gel spots from two distantly related mo

Group A Streptococcus (GAS) infection by serotype M18 strains causes acute rheumatic fever (ARF) and can lead to pediatric heart disease. In the April 2 Proceedings of the National Academy of Sciences, James Smoot and colleagues at the National Institute of Allergy and Infectious Diseases report the genome sequence of a GAS strain (MGAS8232) isolated from a patient with ARF (Proc Natl Acad Sci USA 2002, 99:4668-4673).Smoot et al. compared the 1.9 Mb genome with a closely related strain (the M1 s

The origin of the vertebrate jaw is something of a mystery. In the March 28 Nature, Martin Cohn from the University of Reading suggests that Hox gene expression may be at the origin of jaw evolution (Nature 2002, 416:386-387).In jawed vertebrates (gnathostomes) the jaw and pharyngeal skeleton is derived from migrating cranial neural crest cells. Cohn studied the lamprey, a primitive jawless fish related to gnathostomes, in which the branchial arch is also neural-crest-derived. He cloned lamprey

In a paper published on March 28 in Sciencexpress, Rachel Brem and colleagues describe how linkage analysis and gene expression profiling can be combined to dissect transcriptional regulatory networks in the budding yeast, Saccharomycescerevisiae (DOI:10.1126/science.1069516).Brem et al. crossed two yeast strains; a laboratory strain BY and a wild isolate RM from an Italian vineyard. Microarray analysis revealed 1528 genes expressed differentially between the two parent strains. They then used a

Replicative senescence is associated with telomere shortening and the loss from the ends of chromosomes of about 100 bp per population doubling. In March 19 Science, Jan Karlseder and colleagues at Rockefeller University claim that the state of the ends, rather than telomere loss, determines the induction of senescence (Science 2002, 295:2446-2449).Karlseder et al. studied primary human fibroblasts expressing TRF2, a sequence-specific DNA-binding protein that binds to telomeric repeats. TRF2 ove

Large families of RNA molecules of 21-22 nucleotides, called microRNAs, have been found in a number of species. In an Advanced Online Publication from Nature Genetics, Eric Lai from the University of California at Berkeley, describes a family of microRNAs in Drosophila (Nat Genet 2002, DOI:10.1038/ng865).He found that 11 Drosophila microRNAs are complementary to the K-box motif (cUGUGAUa), Brd box (AGCUUUA) and GY box (uGUCUUCC) motifs present in the 3' untranslated regions (UTRs) of several bas