In the early online edition of Nature this week, scientists at the Max Planck Institute for Molecular Biomedicine report generating "one-factor human iPS cells." By expressing only OCT4 — one of the four transcription factors that have been used to reprogram mouse and human somatic cells into iPS cells — they were able to transform human fetal neural stem cells into iPS cells. "One-factor human NiPS cells resemble human embryonic stem cells in global gene expression profiles, epigenetic status, as well as pluripotency in vitro and in vivo," they say in the abstract.
In this week’s issue, a column by David Goldston checks in on the first hints of the Obama Administration's 2011 budget proposal, saying it's made "universities' lobbyists jittery," he writes. "What is striking about the 4 August memo is its emphasis on tightly linking research programmes to solving what are pointedly labelled as 'practical challenges', its focus on evaluating programme outcomes with data that would be made publicly available, and its call for shifting money away from 'lower priority' areas."
Two papers in the current issue show that iPS cells can produce live mice. Scientists at the Chinese Academy of Sciences and Shanghai Jiao Tong University used forced expression of the four pluripotency transcription factors to generate several iPS cell lines that could be reared up into live, fertile mice. Over at the Scripps Research Institute in La Jolla, California, researchers report fertile adult mice from iPS cells that were created through reprogramming mouse embryonic fibroblasts. "Producing adult mice derived entirely from a reprogrammed fibroblast shows that all features of a differentiated cell can be restored to an embryonic level of pluripotency without exposure to unknown ooplasmic factors," they say.
Over at Nature Genetics, Evan Eichler led work to create an algorithm called mrFAST to map short, next-gen sequencing reads in order to predict copy number variation. In validating the program on three human genomes, they found that there is an average of 73 to 87 genes that vary in copy number between any two people and that these "genic differences overwhelmingly correspond to segmental duplications."