biostudies-literatureChapman JAAustrian Science Fund FWFNCRR NIH HHS592-6https://www.ebi.ac.uk/biostudies/studies/S-EPMC4479502biostudies-literatureUnknown464(7288)The freshwater cnidarian Hydra was first described in 1702 and has been the object of study for 300 years. Experimental studies of Hydra between 1736 and 1744 culminated in the discovery of asexual reproduction of an animal by budding, the first description of regeneration in an animal, and successful transplantation of tissue between animals. Today, Hydra is an important model for studies of axial patterning, stem cell biology and regeneration. Here we report the genome of Hydra magnipapillata and compare it to the genomes of the anthozoan Nematostella vectensis and other animals. The Hydra genome has been shaped by bursts of transposable element expansion, horizontal gene transfer, trans-splicing, and simplification of gene structure and gene content that parallel simplification of the HNatureThe dynamic genome of Hydra.PMC4479502R24 RR015088P 20734P 21108Walenz BHirose MHayakawa EGee LRattei TViswanathan LDFraune SHolstein TWWeinmaier THellsten UKhalturin KBalasubramanian PGBottger AShu SHayakawa SDisbennett KKibler DFGuder CHobmayer BWatanabe HDana CEMartinez DEBertulat BVenter JCSalvenmoser WGojobori THwang JSAufschnaiter RHampson SEChapman JAIkeo KBusam DAugustin RProchnik SENakamura YWheeler BMOzbek SSumin NPeterson KJSimakov OMitros TBode HRFranke AHemmrich GPfannkoch CLindgens DWigge PAStrausberg RLSutton GGGoodstein DMTakahashi TWolf AHeimberg AMGorny AKBlumberg BEder MKBosch TCRokhsar DSTechnau UBorman JFujisawa TKawashima TDavid CNNishimiya-Fujisawa CPutnam NHLaw LTischler PKirkness EFZhang XRemington KAOgura ASteinmetz PRPeng JSteele REfalseThe dynamic genome of Hydra.The freshwater cnidarian Hydra was first described in 1702 and has been the object of study for 300 years. Experimental studies of Hydra between 1736 and 1744 culminated in the discovery of asexual reproduction of an animal by budding, the first description of regeneration in an animal, and successful transplantation of tissue between animals. Today, Hydra is an important model for studies of axial patterning, stem cell biology and regeneration. Here we report the genome of Hydra magnipapillata and compare it to the genomes of the anthozoan Nematostella vectensis and other animals. The Hydra genome has been shaped by bursts of transposable element expansion, horizontal gene transfer, trans-splicing, and simplification of gene structure and gene content that parallel simplification of the H2010-01-01T00:00:00Z2010 Mar2026-05-30T11:22:26.853Z2026-04-08T07:10:45.696ZS-EPMC44795022022879210.1038/nature08830