Quercus robur Genome sequencing and assembly

On May 12, 1800, Napoleon Bonaparte and his troops crossed what is now the Lausanne University campus, on their way to conquer Italy. A 22-year old oak tree was standing next to the paved road, or was transplanted in honour of the emperor's passage, and subsequently baptised "Napoleon oak" by the academic community. By now, the genome of this magnificent 238-year-old specimen is assumed to have accumulated somatic mutations due to replication errors and exposure to the environment. Estimates of rate of somatic mutations in eukaryotes, including the model plant species Arabidopsis thaliana, have been obtained from mutation accumulation lines with short-generation times and grown in the laboratory1-4. However, the extent of somatic mutations in a naturally occurring old tree is totally unknown. Here we sequence and compare genomes of two distant branches of the Napoleon oak. We find a surprisingly low number of single-nucleotide variants (SNVs) that may underlie a growth process where stem cells are protected from genetic variation, analogous to germ cells in animals.