This family consists of several Gypsy/Env proteins from Drosophila and Ceratitis fruit fly species. Gypsy is an endogenous retrovirus of Drosophila melanogaster. Phylogenetic studies suggest that occasional horizontal transfer events of gypsy occur between Drosophila species. Gypsy possesses infective properties associated with the products of the envelope gene that might be at the origin of these interspecies transfers. This family contains many members with full-length matches; however, it also includes a number of very short sequences and short matches of sequences with other unrelated domains on them, which cannot be excluded. These matches may represent remnants of once-functional genes.