Retroviral envelope proteins mediate receptor recognition and membrane fusion during early infection. Endogenous envelope proteins may have kept, lost or modified their original function during evolution (By similarity). Cerebellum and testis. Intergenic, closest flanking genes being GSTM1 and GSTM5. Belongs to the beta type-B retroviral envelope protein family. HERV class-II K(HML-8) env subfamily. Truncated; premature stop codon in the surface protein. No predictable signal peptide. Product of a dubious gene prediction.