ERVW-1 and systemic lupus erythematosus: To study the role of this envelope protein in lupus, we cloned an N-terminal glutathione-S-transferase (GST)–tagged 1,086-bp SU of the envelope protein beginning at the internal methionine, which generates a coding sequence without stop codons and is identical to the sequence in the human proteome database (NX_P61567).