The eukaryotic LigT-like family is typified by the human CGI-18 gene and is represented in plants, animals and fungi. The maximum likelihood tree revealed that the 2H phosphoesterases encoded by some coronaviruses and rotaviruses, are the closest relatives of these eukaryotic LigT-like family. Orthologs of CGI-18 in animals and plants are fused to an RNA binding KH domain, whereas one of its human-specific paralogues, LENG9, is fused to another RNA binding domain, zinc chelating CCCH-like fingers. These domain architectures suggest that these eukaryotic LigT-like proteins may participate in RNA metabolism [<cite idref="PUB00013642"/>].