FBN1 and obesity due to melanocortin 4 receptor deficiency: Asprosin is a novel adipokine that is encoded by the last two exons (65, 66) of the FBN1 gene on chromosome 15 q21.1, and is cleaved from the C-terminus of the fibrillar precursor (FBN1 gene encoding) by Flynn protease [18], asprosin is associated with the metabolic syndrome features like glucose and lipid metabolism, insulin resistance, obesity and inflammation [19].