Fig. 1
From: Classification and characterization of human endogenous retroviruses; mosaic forms are common
Some retroviral genetic structures encountered during this work. a Prototypical provirus, with genes and subgenes. Abbreviations are explained in the text, and/or in [35]. dUTPase occurred in either the protease or polymerase genes. b Partial, truncated, provirus. c Provirus with secondary integration, often an LTR in sense or antisense direction. d Recombinant provirus with contributions from different ERVs, in this case a Harlequin element. e Processed pseudogene, i.e. a reverse transcribed genomic retroviral mRNA. Processed pseudogenes were not distinguished from proviruses in the present work