Wallinder et al. [64] showed that patients with small AAAs had increased levels of the enzyme glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) compared with controls without aneurysm by using a proteomic approach, providing some evidence of the value of GPI-PLD as a novel potential plasma biomarker for the detection of AAAs [64]. This evidence concerns the gene GPLD1 and achalasia-alacrima syndrome.