In this week's Nature, two separate research groups report on the evolution and function of the Y chromosome in male mammals. In one paper, a team from the University of Lausanne and elsewhere describe the use of a novel sequencing technique to examine Y evolution across 15 mammals, showing the origins of the chromosome in placental and marsupial mammals, which emerged just before the split of these lineages around 180 million years ago. In another paper, a group led by Massachusetts Institute of Technology scientists show that dosage constraints are an important selective pressure that preserves the surviving ancestral genes and suggests that Y genes are vital for male viability.
GenomeWeb Daily News has more on these studies here.
Also in Nature, a multi-institute team of investigators argue for the need for clear guidelines to help distinguish disease-causing genetic variants from other variants in the human genome. The editorial highlights the challenges in assessing sequence variants in human disease and offers recommendations for summarizing confidence in the link between variants and diseases. "Objective, systematic, and quantitative evaluation of the evidence for pathogenicity and sharing of these evaluations and data amongst research and clinical laboratories will maximize the chances that disease-causing genetic variants are correctly differentiated from the many rare non-pathogenic variants seen in all human genomes," the team says.
Meanwhile, in Nature Biotechnology, a team from Carnegie Mellon University presents Sailfish, a computational method for quantifying the abundance of previously annotated RNA isoforms from RNA-seq data. By avoiding mapping reads, the tool provides quantification estimates much faster than do existing approaches without loss of accuracy.