Consequently, the molar IGF1/IGFBP3 ratio showed no differences with age but a significant decrease in PXE patients over 45 years compared to appropriate healthy controls (PXE: 0.22 ± 0.01; control: 0.31 ± 0.03; p≤0.05) (Fig. 3C). This evidence concerns the gene IGF1 and Pseudoxanthoma elasticum.