For instance, due to a significant “deficiency” of protein products of genes (CPNE1, EDEM2, PROCR, UQCC1), their expression can be extremely reduced in individuals carrying reduced fat mass and a low-productive G allele rs143384 (KOA risk factor in individuals without obesity), which may, as an important pathogenetic factor, significantly contribute to the development of KOA. This evidence concerns the gene UQCC1 and obesity due to melanocortin 4 receptor deficiency.