In Science this week, the HUGO Pan-Asian SNP Consortium presents results of their study looking at what genetic variation can reveal about migration patterns. Using microarrays to find variation in almost 2,000 people representing 73 Asian and two non-Asian populations, they found that "most genetic clusters corresponded to language groups" and that an "influx of individuals from Southeast Asia contributed genetically to many populations found in East Asia today," says a story at our sister publication, GenomeWeb Daily News. A Science news story offers more details.
In other interesting work, scientists led by senior author Eric Olson at the University of Texas Southwestern Medical Center found that an miRNA expressed only in skeletal muscle, miR-206, helps not only to slow the progression of amyotrophic lateral sclerosis but also aids in the regeneration of neuromuscular synapses. They found that miR-206 is "dramatically induced" in a mouse model of ALS and when they knocked it out, the disease progressed faster. They believe that miR-206 operates in part through histone deacetylase 4 and fibroblast growth factor signaling pathways. "Thus, miR-206 slows ALS progression by sensing motor neuron injury and promoting the compensatory regeneration of neuromuscular synapses," they write. A perspective offers details.
In screening for proteins that interact with metabotropic glutamate receptor 5 (mGluR5), which is critical to proper CNS function and a target for treating schizophrenia, scientists led by those at Rockefeller University identified Norbin, a neuron-specific protein. This protein "physically interacts with mGluR5 in vivo, increases the cell surface localization of the receptor, and positively regulates mGluR5 signaling." When they deleted the gene in mice, they found that it induces a behavioral phenotype similar to that of a mouse model of schizophrenia.
A review by historian Jim Endersby at the University of Sussex takes a look at the practice of taxonomy in the 19th century, and the divide between "lumpers" and "splitters." Joseph Dalton Hooker, who at the time was the director of the Royal Botanic Gardens in London and a close friend of Darwin's, embodied in his practice the generally held idea that natural selection wouldn't have much of an affect on taxonomic grouping of species. Hooker supported lumping all varieties of a species into one group, whereas Darwin's theories incorporated dividing species endlessly.