The only known GFAP-isoforms that were annotated in this dataset were GFAPα and GFAPδ. Interestingly, while canonical GFAPα expression is indeed significantly decreased in grade IV astrocytoma compared to grade II (45%, FDR = 1.20E-4; Figure 1A) and to grade III (55%, FDR = 8.4E-4; Figure 1A), the expression of the alternative splice variant GFAPδ is not different between astrocytoma grades (Figure 1B). Here, GFAP is linked to astrocytoma (excluding glioblastoma).