Telomerase activity was found in gonad extracts of the jellyfish
Aurelia aurita and the ctenophore Pleurobranchia pileus, but not in
other cnidarians such as Cyanea, Chrysaora, Hydra and Nematostella
(Traut et al., 2007). While Koziol et al. (1998) found telomerase activity
in the sponge Suberites domuncula, Traut et al. (2007) failed to detect
telomerase activity in S. domuncula and suggested that the failure
could have been due to technical reasons or because cellular
concentration of telomerase or the proportion of telomerase-positive
cells was low in their samples.