Research on a unique vertebrate called the sea lamprey shows that more than a thousand genes are shed during its early development. These genes are paradoxically lost all throughout the developing embryo except in a specialized compartment called "primordial germ cells" or PGCs. The PGCs can be thought of as embryonic stem cells and are used, ultimately, for making the next generation of lampreys. Based on computational analysis, a significant number of genes that are lost in the embryo have signatures of "pluripotency," which suggests that they could also have undesirable effects if they were inadvertently turned on in the body. In effect, by undergoing programmed genome rearrangement and gene loss during embryogenesis, the sea lamprey "seals" the genes away in the small germline compartment so they cannot be misexpressed and thereby create untoward problems (such as development of cancer, for example). The study was completed at the Benaroya Research Institute at Virginia Mason (BRI) and recently published as a featured article in Current Biology, along with an outside commentary highlighting its biological importance.
The article authors are Jeramiah Smith, PhD, former postdoctoral fellow at BRI and now Assistant Professor of Biology at the University of Kentucky; Chris Amemiya, PhD, Principal Investigator at BRI and Professor of Biology, University of Washington; Evan Eichler, PhD, University of Washington Genome Sciences Professor; and Carl Baker, Research Scientist, University of Washington.