Finally, several studies and meta-analyses have described other possible biomarkers for stroke diagnosis, including matrix metalloproteinase 9 (MMP-9) (83, 84), Brain natriuretic peptide (BNP) (85), N-methyl-D-aspartate receptor proteins (86) and apolipoproteins (87, 88), which may also help to discriminate between atheroembolic stroke and other main etiologies (89). This evidence concerns the gene NPPB and stroke disorder.