The recently uncovered hotspot mutations in the fibroblast growth factor receptor 1 (FGFR1), leading to hyperactivity along the MAPK axis identified in PA, are also identified in a rare subset of pediatric HGA of the thalamus and notably seem invariably associated with H3.3 K27M mutations [35]. This evidence concerns the gene FGFR1 and human granulocytic anaplasmosis.