JAK2 and myeloproliferative disorder: Initially developed for myeloproliferative diseases and large granular leukaemia, respectively, for somatic JAK2 and STAT3 gain of function (GOF) mutations, those treatments have been subsequently approved based on the results of clinical trials in the context of inflammatory or auto-immune diseases [12], e.g., rheumatoid arthritis and psoriasis in adult patients.