Daniel Rokhsar
Comparative analysis of genomic diversity across animals and their relatives. The first signs of animal life appear in the fossil record ~600 million years ago. Modern survivors of these early progenitors include sponges, placozoans, cnidarians (anemones, jellyfish, hydra), ctenophores (comb jellies), and bilaterally symmetric animals (flies, snails, worms, humans). Each of these modern phyla retains some of the genomic dowry inherited from the early animals, elaborated on (and sometimes overwritten by) subsequent evolutionary innovations (and losses). By comparing genomes, we not only characterize the basic biochemical, physiological, and developmental "tool kits" of animals, but also map out their evolutionary history, and infer evolutionary mechanisms for the emergence of animal diversity complexity from more humble unicellular beginnings. Surprisingly, we are finding evidence for deep conservation of exon-intron gene structure, gene content and even chromosomal linkages and are using these features to try to reconstruct aspects of ancestral animal genomes.
In the News
Study helps map path to improved cassava production
A new analysis of the genetic diversity of cassava will help improve strategies for breeding disease resistance and climate tolerance into the root crop, a staple and major source of calories for a billion people worldwide.
What do leeches, limpets and worms have in common?
Leeches, despite the yuck factor, have captured the hearts of two University of California, Berkeley, scientists who are part of a team that this week is publishing the leech’s complete genome sequence.
Genome of ancient sponge reveals origins of first animals, cancer
A team led by Daniel Rokhsar has published a draft genome sequence of the sea sponge, an organism that wasn't recognizied as an animal until the 19th century. The genome gives insight into the origins of multicellular animals and cancer.
Scientists report first genome sequence of frog
The African clawed frog, Xenopus, has helped scientists understand how embryos develop and the many chemical reactions going on inside dividing cells. Now, scientists report the first draft genome sequence of Xenopus, setting the stage for a more complete genetic analysis of this popular frog.