Pedigrees of 4 MPN families (F1, F2, F3, and F4) showing that TET2 mutations do not segregate with the MPN phenotype. Filled symbols represent patients; their clinical phenotype is indicated below. Under each symbol, the first top line represents the phenotype at the time of diagnosis; the second line, the evolution (blank where there is none); the third line, the JAK2^V617F status (V617F when the mutation was found; – otherwise); and the fourth line, any TET2 mutation. Mutations are annotated in amino acid one-letter code. nd indicates not done.