Highly read on dev.biologists.org in April

The genetic mechanisms that regulate how an organ of the immune system forms are conserved between mice and humans.

Tucked inside the ribcage and near the heart, the thymus screens out self-attacking white blood cells. Although molecular and gene-expression patterns that govern the formation of the organ can be readily studied in mice, human studies are generally limited to examining tissue samples under a microscope. Thus, similarities between the species are difficult to assess. Clare Blackburn at the University of Edinburgh, UK, and her team used genetic analysis on tissue from human fetuses. They showed that, in contrast to previous findings, the thymus derives from the same embryological structure in humans as it does in mice. In addition, a collection of genes critical to the organ's development are expressed at similar times in both species, further validating the mouse as a model for thymus development

Development 140, 2015–2026 (2013)