Frequently mutated genes in the JAK/STAT signaling pathway identified by targeted capture sequencing in PTCLs. (A) Distribution of mutations across PTCL subtypes (ALCL, CTCL, NKTL, and PTCL-NOS). The top 36 most frequently mutated genes are shown with the last row indicating the first gene with 2 recurrent mutations. The bar on the right represents the number of samples with mutations, and the bar on the top represents the number of mutations in each sample. Samples having no mutations were excluded. (B) Locations of novel, previously studied, and hotspot mutations in the coiled-coil α domain, DNA binding domain and SH2-domain of STAT3 in PTCLs. STAT3 mutations p.R278H,⁷⁹  p.H410R,⁶³  and p.Q344H⁸⁰  were previously reported in autoimmune lymphoproliferative syndrome, large granular lymphocyte leukemia, and patients with lymphoproliferation and childhood-onset autoimmunity, respectively.