Specifically, homozygous inactivating mutations of the matrix metalloproteinase 2 (MMP2), MMP14, or SH3PXD2B genes may cause defective collagen remodeling (de Vos et al., 2019) and result in the allelic variants (Zankl et al., 2007) of MONA (multicentric osteolysis, nodulosis and arthropathy) (Bhavani et al., 2021), Torg (Zankl et al., 2007) or Winchester (Evans et al., 2012) syndrome. The gene discussed is MMP14; the disease is arthropathy.