MMP9 and obesity due to melanocortin 4 receptor deficiency: We also discovered 14 hub genes, including TYROBP, CD44, BGN, FCGR3A, CD53, CXCR4, FN1, SPP1, IGF1, CCND1, MMP9, IL2RG, IL6 and CTGF, which were crucial in the development of CC and obesity.