We describe the second example of red blood cells (RBCs) with the Lu:–7 phenotype in a 37-year-old Latino female (SA). Her RBCs were nonreactive with anti-Lu7 (Mrs. GA) but were reactive with all other antibodies to high-prevalence antigens tested, including those in the Lutheran blood group system. No Lu:–7 RBCs were available for testing. SA’s serum was nonreactive by the indirect antiglobulin test against (1) recessive and dominant Lu(a–b–) RBCs and (2) trypsin-treated or