The JAK2V617F mutation is present in most patients with polycythemia vera (PV) and in some patients with essential thrombocythemia (ET) and myeloid metaplasia/ myelofibrosis (MMM). We sought to investigate the relationship between granulocyte clonality and JAK2V617F allelic ratio. A total of 168 of 190 female patients were informative for a clonality assay at the HUMARA locus; 80% of MMM, 75% of PV, and 67% of ET patients demonstrated clonal granulopoiesis. The JAK2V617F allele was detected by quantitative real-time polymerase chain reaction (PCR) in 99% of PV, 72% of ET, and 39% of MMM. A correlation between clonality and JAK2V617F allelic ratio was demonstrated for PV (P < .001) but not for ET or MMM (both P > .6). These data suggest that acquisition of the JAK2V617F mutation may be sufficient for the development of PV, but additional genetic events are necessary in ET and MMM. In addition, some ET and MMM patients with clonal granulopoiesis have somatic mutations other than JAK2V617F. IntroductionIn 1951, Dr William Dameshek classified polycythemia vera (PV), essential thrombocythemia (ET), myeloid metaplasia/myelofibrosis (MMM), and chronic myelogenous leukemia (CML) as phenotypically related myeloproliferative disorders (MPDs). 1 The molecular pathogenesis of BCR-ABL-negative MPDs was poorly understood until the recent identification of the JAK2V617F activating mutation. 2-8 JAK2V617F confers factor-independent growth and erythropoietin hypersensitivity to hematopoietic cells, 2,3 and expression of JAK2V617F in a murine bone marrow transplantation model results in erythrocytosis. 3 These data suggest that acquisition of JAK2V617F is an important pathogenetic event in JAK2V617F-positive MPDs. Nonetheless, some PV, ET, and MMM patients are JAK2V617F negative, as assessed by DNA resequencing. There are several potential explanations for this observation, including mutations in other genes that phenocopy JAK2V617F. Granulocytes from some patients with PV and ET are polyclonal, 9,10 and thus sequence analysis of granulocyte DNA may underestimate the true frequency of the JAK2V617F allele. Although granulocyte clonality and JAK2V617F mutational status were reported in ET, 11 no study has investigated the relationship between the acquisition of JAK2V617F and the emergence of clonal hematopoiesis in PV, ET, and MMM. We therefore investigated the relationship between clonality and JAK2V617F allelic ratio in MPDs. Study design Harvard Myeloproliferative Disorders StudyThe Harvard Myeloproliferative Disorders Study enrolled patients with PV, ET, and MMM to collect clinical information and biologic samples. 2 All subjects provided informed consent. Approval for the studies was obtained from the Dana-Farber Cancer Institutional Review Board. HUMARA clonality assay and X-inactivation ratio determinationPolymerase chain reaction (PCR) amplification of the polymorphic CAG repeat at the HUMARA locus 12-14 was performed in tandem on undigested (6-FAM-labeled primer) and on HpaII-digested (HEX-labeled primer) DNA. PCR produc...

We study a class of simulated annealing algorithms for global minimization of a continuous function defined on a subset of We consider the case where the selection Markov kernel is absolutely continuous and has a density which is uniformly bounded away from 0. This class includes certain simulated annealing algorithms recently introduced by various authors. We show that, under mild conditions, the sequence of states generated by these algorithms converges in probability to the global minimum of the function. Unlike most previous studies where the cooling schedule is deterministic, our cooling schedule is allowed to be adaptive. We also address the issue of almost sure convergence versus convergence in probability.