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Contrary to Genentech's claims, turning over all in vitro diagnostics to the US Food and Drug Administration (FDA) is the wrong approach to achieve better clinical validation of tests.
The Obama administration looks to be a welcome shot in the arm for the scientific endeavor, but the current economic crisis is likely to keep several issues of key interest to biotech firmly on the back burner.
Only a subset of genetic variants can be examined in genome-wide surveys for genetic risk factors. How can a fixed set of markers account for the entire genome by acting as proxies for neighboring associations?
Goraczniak et al. introduce a gene-silencing method that uses 'U1 adaptors' to block polyadenylation of pre-mRNA in the nucleus. Silencing is stronger when U1 adaptors are combined with siRNAs than when either is used alone.
Keng et al. characterize the mouse hepatocellular carcinoma genome by using tissue-specific recombinase expression to restrict mobilization of the Sleeping Beauty transposon to the liver. High throughput sequencing of >100,000 insertions sites in mouse tumor nodules identifies potential therapeutic targets.
Chambers et al. present an improved method for neural differentiation of human pluripotent stem cells that avoids the use of stromal feeder cells and embryoid bodies. By combining two inhibitors of SMAD signaling, the protocol generates neural cells with an efficiency of >80%.
Teratoma formation is a safety concern for any therapeutic strategy involving human embryonic stem cells. Blum et al. characterize teratomas derived from mouse and human embryonic stem cells and uncover a key role for the oncofetal gene survivin.
Lam and Joyce describe a new approach to ligand detection based on two cross-replicating RNA ligases with allosteric ligand-binding domains. The ligases amplify exponentially at a rate dependent on ligand concentration—a system analogous to qPCR for detection of small molecules and proteins.