Bright field microscopy analysis of Prussian blue-positive hemosiderin deposits and podocalyxin-positive capillaries revealed perivascular hemosiderin deposits in ALS subjects, but not controls, typically 10–50 μm in diameter predominately surrounding capillaries (≤8 μm in diameter) (Fig. 2a). This evidence concerns the gene PODXL and amyotrophic lateral sclerosis.