RT Journal
A1 Sahm, Arne
A1 Riege, Konstantin
A1 Groth, Marco
A1 Bens, Martin
A1 Kraus, Johann
A1 Fischer, Martin
A1 Kestler, Hans
A1 Englert, Christoph
A1 Schaible, Ralf
A1 Platzer, Matthias
A1 Hoffmann, Steve
T1 Hydra has mammal-like mutation rates facilitating fast adaptation despite its nonaging phenotype
JF Genome Research 
JO Genome Research 
YR 2024 
FD December 01 
VO 34 
IS 12 
SP 2217 
OP 2228 
DO 10.1101/gr.279025.124 
UL http://genome.cshlp.org/content/34/12/2217.abstract 
AB Growing evidence suggests that somatic mutations may be a major cause of the aging process. However, it remains to be tested whether the predictions of the theory also apply to species with longer life spans than humans. Hydra is a genus of freshwater polyps with remarkable regeneration abilities and a potentially unlimited life span under laboratory conditions. By genome sequencing of single cells and whole animals, we found that the mutation rates in Hydra’s stem cells are even slightly higher than in humans or mice. A potential explanation for this deviation from the prediction of the theory may lie in the adaptability offered by a higher mutation rate, as we were able to show that the genome of the widely studied Hydra magnipapillata strain 105 has undergone a process of strong positive selection since the strain's cultivation 50 years ago. This most likely represents a rapid adaptation to the drastically altered environmental conditions associated with the transition from the wild to laboratory conditions. Processes under positive selection in captive animals include pathways associated with Hydra’s simple nervous system, its nucleic acid metabolic process, cell migration, and hydrolase activity.