library_construction_protocol: Peripheral blood of patients with germline TNFAIP3 mutations and healthy control individuals was collected. Peripheral blood mononuclear cells (PBMCs) were isolated from peripheral blood by density-gradient centrifugation using Biocoll separation solution. Genomic DNA of PBMCs and lymphoma tissue was isolated using the GenElute mammalian genomic DNA miniprep kit The rearranged V, D and J gene segments of the IGH and TRB loci were amplified in a multiplex PCR using BIOMED2-FR1 (IGH) or -TRB-B primer pools together and 250 ng of genomic DNA. The primers were purchased from Metabion International AG. As described in17, two consecutive PCR reactions were performed to generate IGH and TRB fragments tagged with Illumina-compatible adapters.