Among immune system diseases like osteoarthritis (20) and rheumatoid arthritis (21), septicemia (22), atherosclerosis, osteoporosis (23), diabetes (18), atopic dermatitis (24), epithelial ovarian cancer (25), and obesity (26), LECT2 can activate and recruit immune cells to regulate inflammatory responses and immune responses (9). The gene discussed is LECT2; the disease is obesity due to melanocortin 4 receptor deficiency.