Mice lacking MAN2A1 exhibit a deficiency in N-glycans on red blood cells, resulting in anemia and the development of a late-onset autoimmune disease that closely resembles systemic lupus erythematosus (SLE) (Chui et al., 1997; Chui et al., 2001). This evidence concerns the gene MAN2A1 and systemic lupus erythematosus.