By applying a statistical model to seven complete human genome sequences, the Wellcome Trust Sanger Institute's Heng Li and Richard Durbin have generated a "detailed history of human population sizes between approximately ten thousand and a million years ago," which they present in a paper published online in advance in Nature this week. In applying the pairwise sequentially Markovian coalescent model applied to the published genomes of a Chinese male, a Korean male, three European individuals, and two Yoruba males, Li and Durbin predict that "the differentiation of genetically modern humans may have started as early as 100-120 kyr [thousand years] ago, but considerable genetic changes may still have occurred until 20-40 kyr ago." Our sister publication GenomeWeb Daily News has more on this study here.
In another Nature paper published online in advance this week, a team led by investigators at Stanford University reports that "expression of miR-9/9* and miR-124 in human fibroblasts induced their conversion into neurons, a process facilitated by [the transcription factor] NEUROD2." The Stanford-led team also shows that the further addition of the transcription factors ASCL1 and MYT1L "enhances the rate of conversion and the maturation of the converted neurons, whereas expression of these transcription factors alone without miR-9/9*-124 [is] ineffective."
Researchers in Germany and Spain this week show that "multi-domain conformational selection underlies pre-mRNA splicing regulation by [human] U2AF." In their paper, the researchers discuss the molecular mechanism that underlies U2AF's recognition of the 3'-splice-site-associated polypyrimidine tract RNA, in which they found "mutations that shift the conformational equilibrium without directly affecting RNA binding modulate splicing activity accordingly."
Over in Nature Genetics, an international team led by researchers at the Université de Montréal suggests that de novo mutations — in particular, 15 that it has identified — "may account for some of the heritability reported for schizophrenia while providing a list of genes possibly involved in disease pathogenesis." Of the 15 de novo mutations the team reports, four are nonsense mutations, "which is more than what is expected by chance."