Treatment with the leptin antagonist increased average daily food intake in both NZW and NZBWF1 animals (Control-vehicle: 3.6 ± 0.1 vs. Control-LA: 4.5 ± 0.1 g/day, P=0.006; SLE-vehicle: 3.4 ± 0.1 vs. SLE-LA: 4.5 ± 0.1 g/day, P<0.0001). The gene discussed is LEP; the disease is systemic lupus erythematosus.