In a Nature paper published online in advance this week, Ion Torrent's Jonathan Rothberg and his colleagues discuss technical details of the firm's "technology in which scalable, low-cost semiconductor manufacturing techniques are used to make an integrated circuit able to directly perform non-optical DNA sequencing of genomes." To demonstrate the technology's performance, the Ion Torrent team reports using it to sequence three bacterial genomes and to produce a low-coverage sequence of Gordon Moore's genome. Our sister publication GenomeWeb Daily News has more on this paper.
Researchers at the University of Minnesota and elsewhere show that the transcription factor "DMRT1 prevents female reprogramming in the postnatal mammalian testis" in a paper published online in advance this week. Further, the team reports that Dmrt1 is "essential to maintain mammalian testis determination" and adds that an antagonistic relationship exists between Dmrt1 and Foxl2 for the control of gonadal sex in mammals, and potentially in other groups.
Elsewhere in Nature, a trio of investigators at the California Institute of Technology suggests that "DNA strand displacement cascades could be used to endow autonomous chemical systems with the capability of recognizing patterns of molecular events, making decisions and responding to the environment." In its paper, the Caltech team discusses building upon DNA computing and strand-displacement circuitry to "systematically transform arbitrary linear threshold circuits" using simple DNA gate architecture, as described by two of the study's co-authors in Journal of the Royal Society Interface in February. The team reports its construction of "four fully connected artificial neurons that, after training in silico, remembers four single-stranded DNA patterns and recalls the most similar one when presented with an incomplete pattern."
Over in Nature Genetics, a team led by researchers at the University of California, Los Angeles, presents an "approach for constructing high-resolution maps of relative recombination rates based on the observation of ancestry switch points among admixed individuals," which it has applied to SNP data from 2,565 African Americans and 299 African Caribbeans to elucidate "evidence of fine-scale differentiation in recombination rates" the populations. In its paper, the UCLA-led team says that "overall, the admixed map is well-predicted by the average proportion of admixture and the recombination rate estimates from the source populations."