UCL Division of Biosciences


GEE Seminar - Prof Mark Blaxter, Wellcome Sanger Institute

08 March 2023, 12:00 pm–1:00 pm


Title: ‘Reference genome sequences across the Tree of Life - a treasure trove for evolution and conservation’

Event Information

Open to

All | UCL staff | UCL students | UCL alumni




Amy Godfrey


Roberts Building

Academic Host: Aida Andres
Abstract: The Tree of Life: new genomes and new biologyEarth's biosystems are under increasing threat and new toolkits are needed to both understand the origins of diversity and provide potential routes to recovery and survival. The Tree of Life programme at the Wellcome Sanger Institute has embarked on a long-term project to sequence as much of the planet's eukaryotic biodiversity as possible, to provide an openly-accessible, foundational resource for conservation, bioindustry and basic science. We are involved in several major projects including Darwin Tree of Life (all British and Irish species), Aquatic Symbiosis (eukaryotes living with microbial symbionts), European Reference Genome Atlas and others. With partners across the world, we have built a genome engine that finds, identifies, extracts and sequences any species, and through improved assembly and curation processes delivers chromosomally-complete reference genome sequences. We currently have released over 700 genomes: plants, fungi, protists and animals.In amongst this wealth of data - of unprecedented quality and breadth - we have been exploring new genome biology. I will present one such discovery: the finding of programmed DNA elimination in the somatic cells of many species of free-living nematodes. This process means that the soma has a different DNA content (and can even have a different karyotype) from the germline of an individual. I will show how reference quality genomes have allowed us to identify mechanistic aspects of the process, and start to elucidate the "why" of this trait.

About the Speaker

Professor Mark Blaxter

Senior Group Leader at Wellcome Sanger Institute

 I am Programme Lead for the Sanger Institute's new Tree of Life Programme. ToL has as an overarching goal the sequencing to high quality of all species on Earth. At ToL in Sanger we are responsible for developing the engines needed to generate very high quality genome assmblies, including developing new methods and computer tools. We will be working closely with other large scale genome sequencing projects worldwide, inlcuding the Earth BioGenome Project, the Vertebrate Genomes Project and others, to deliver a global genomic resource that benefits all. We will use these genomes to build the tree of life, revealing how organisms are related, and identifying where, when and how speciation happens. We will explore the genes present in the thousands of genomes: how do these evolve through time? We will explore the hidden world of cryptic species, where organisms that look the same to us are actually independent evolutionary units, and use sequencing as an assay to track species diversity in space and time. We will explore the genomics of symbiosis, where distinct organisms live together.

My background is in the genomics of parasitic nematodes, but I have worked on a wide range of species from viruses to mammals, and on topics ranging from the dynamics of infection in marine algae to the origins of handedness in snails to the evolution of male plumage diversity in birds. 

More about Professor Mark Blaxter