Most studies, that did not differentiated between patients with predominant lipoatrophy, lipohypertrophy, and mixed patterns of fat redistribution, have failed to find significantly lower leptin levels in subjects with HIV lipodystrophy[24,31,32], but when subjects with distinctive lipoatrophy have been studied separately, lower leptin levels in this subgroup of HIV lipodystrophy patients has been observed. The gene discussed is LEP; the disease is lipodystrophy.