Presence of HERV-K14-homologous sequences in various primate species, as revealed by PCR. (Top) Presence of HERV-K14I homologues in hominoids and Old World primates but not in New World primates and prosimians. Specific PCR products of ∼740 bp were amplified from positive species. PCR products in New World primates and prosimians proved to be nonretroviral after being sequenced. The lower PCR yields in lanes Pha and Msp are probably due to suboptimal genomic DNA quality for those species. (Bottom) Similar species distributions of HERV-K14CI homologues, as revealed by a specific PCR product of ∼620 bp. Species abbreviations are as follows. Hominoidea: Hsa (Homo sapiens), Ptr (Pan troglodytes), Ppa (Pan paniscus), Ggo (Gorilla gorilla), and Ppy (Pongo pygmaeus). Old World primates (OWP): Hla (Hylobates lar), Pha (Papio hamadryas), Cgu (Colobus guereza), Mfa (Macaca fascicularis), Mmu (Macaca mulatta), Msp (Mandrillus sphinx). New World primates (NWP): Ase (Alouatta seniculus), Cja (Callithrix jacchus), Ssc (Saimiri sciureus). Prosimian (Pros.): Nyc (Nycticebus coucang).