BRAF gene rearrangements that were indicated in three tumors prompted the discovery of KIAA1549-BRAF fusion transcripts expressed in 10 of 10 grade 1 astrocytomas and in none of the grade 2 to 4 tumors.
As the KIAA1549-BRAF fusion gene is detected at a much lower frequency in diffuse low-grade astrocytomas and survival was much longer than expected in the patients with a 'non-pilocytic' astrocytoma carrying the fusion gene, identification of this fusion gene can be of diagnostic and prognostic value.