In the PNAS Early Edition this week, Jeremy Miller, Steve Horvath, and Daniel Geschwind at the University of California, Los Angeles, report their systems-biology approach, "using weighted gene coexpression network analysis on more than 1,000 microarrays from the brain," to characterize gene expression divergence between mice and humans. Overall, the trio found the "global network properties of the brain transcriptome" to be "highly conserved" between species, although they did identify "several robust human-specific modules, including one strongly correlated with measures of Alzheimer's disease progression across multiple data sets," the authors write.
Investigators at the Institut National de la Recherche Agronomique in France suggest that β-D-glucuronidase "uncovers a core adaptive function of the human intestinal microbiome," in the PNAS Early Edition. In examining the gut microbes of 11 individuals, the team found the β-D-glucuronidases (H11G11-BG) to be present in each. The authors conclude that their functional metagenomic study "revealed a class of BGs that may be part of a functional core specifically evolved to adapt to the human gut environment with major health implications."
Researchers at Affymetrix, the Lawrence Berkeley National Laboratory, and Stanford University present their microarray-based "high-throughput method for analyzing methylation of CpGs in targeted genomic regions" in this week's PNAS. Their new method "relies on selective enrichment of the regions to be assayed by target amplification by capture and ligation" — or mTACL — to generate "quantitatively accurate" and "highly reproducible" measurements using nanogram amounts of DNA. In short, "mTACL is a platform for profiling the state of methylation of a large number of CpG in many samples in a cost-effective fashion," the authors write.
Also in PNAS this week, Mary-Claire King and colleagues at the University of Washington in Seattle report their "detection of inherited mutations for breast and ovarian cancer using genomic capture and massively parallel sequencing," in an effort to determine whether a genomic assay — designed to capture mutations in 21 genes, including BRCA1 and BRCA2 — would be "accurate, thorough, and cost-effective." King et al. write that their approach generated "zero false-positive calls of nonsense mutations, frameshift mutations, or genomic rearrangements for any gene in the test samples."