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Turritopsis dohrnii is the only metazoan able to rejuvenate repeatedly after its medusae reproduce, hinting at biological immortality and challenging our understanding of aging. We present and compare whole-genome assemblies of T. dohrnii and the nonimmortal Turritopsis rubra using automatic and manual annotations, together with the transcriptome of life cycle reversal (LCR) process of T. dohrnii. We have identified variants and expansions of genes associated with replication, DNA repair, telomere maintenance, redox environment, stem cell population, and intercellular communication. Moreover, we have found silencing of polycomb repressive complex 2 targets and activation of pluripotency targets during LCR, which points to these transcription factors as pluripotency inducers in T. dohrnii . Accordingly, we propose these factors as key elements in the ability of T. dohrnii to undergo rejuvenation.

La violencia es considerada una forma de ejercicio del poder que facilita la dominación, opresión o supremacía a quien la ejerce y una posición de sometimiento o sujeción de quien la sufre. En Ecuador, la violencia provocada en el contexto de confinamiento va en aumento, según El ECU 911 hasta el 17 de abril del año 2020 habían aumentado los casos de violencia en un 47%. Objetivo: Examinar en la literatura sobre la Violencia intrafamiliar frente al confinamiento durante la pandemia Covid-19. Se realizó una revisión sistemática de la literatura. La búsqueda se realizó en buscadores oficiales como Science Direct, Redalyc, Scielo, Medigraphic y Scopus. El aumento de violencia intrafamiliar (VI) aumentó en un rango del 28 al 50%. Sólo en Ecuador el incremento de VI aumentó en un 43,4%. Entre los factores que más se asociaron al incremento de VI durante la pandemia del COVID-19 fueron el sexo femenino y el desempleo, otro factor que se identificó, como causante de VI fue el abuso de sustancias, especialmente el alcohol. En conclusión, podemos asegurar de acuerdo con la investigación que la violencia intrafamiliar se incrementó en todo el mundo.

Genomic studies have recently identified RPS15 as a new driver gene in aggressive and chemorefractory cases of chronic lymphocytic leukemia (CLL). RPS15 encodes a ribosomal protein whose conserved C-terminal domain extends into the decoding center of the ribosome. We demonstrate that mutations in highly conserved residues of this domain affect protein stability, by increasing its ubiquitin-mediated degradation, and cell-proliferation rates. On the other hand, we show that mutated RPS15 can be loaded into the ribosomes, directly impacting on global protein synthesis and/or translational fidelity in a mutation-specific manner. Quantitative mass spectrometry analyses suggest that RPS15 variants may induce additional alterations in the translational machinery, as well as a metabolic shift at the proteome level in HEK293T and MEC-1 cells. These results indicate that CLL-related RPS15 mutations might act following patterns known for other ribosomal diseases, likely switching from a hypo- to a hyperproliferative phenotype driven by mutated ribosomes. In this scenario, loss of translational fidelity causing altered cell proteostasis can be proposed as a new molecular mechanism involved in CLL pathobiology.

Multiple myeloma (MM) patients undergo repetitive bone marrow (BM) aspirates for genetic characterization. Circulating tumor cells (CTCs) are detectable in peripheral blood (PB) of virtually all MM cases and are prognostic, but their applicability for noninvasive screening has been poorly investigated. Here, we used next-generation flow (NGF) cytometry to isolate matched CTCs and BM tumor cells from 53 patients and compared their genetic profile. In eight cases, tumor cells from extramedullary (EM) plasmacytomas were also sorted and whole-exome sequencing was performed in the three spatially distributed tumor samples. CTCs were detectable by NGF in the PB of all patients with MM. Based on the cancer cell fraction of clonal and subclonal mutations, we found that ~22% of CTCs egressed from a BM (or EM) site distant from the matched BM aspirate. Concordance between BM tumor cells and CTCs was high for chromosome arm-level copy number alterations (≥95%) though not for translocations (39%). All high-risk genetic abnormalities except one t(4;14) were detected in CTCs whenever present in BM tumor cells. Noteworthy, ≥82% mutations present in BM and EM clones were detectable in CTCs. Altogether, these results support CTCs for noninvasive risk-stratification of MM patients based on their numbers and genetic profile., This study was supported by the Centro de Investigación Biomédica en Red—Área de Oncología—del Instituto de Salud Carlos III (CIBERONC; CB16/12/00236, CB16/12/00369, CB16/12/00489, and CB16/12/00400); by Cancer Research UK [C355/A26819] and FC AECC and AIRC under the Accelerator Award Program; by the Instituto de Salud Carlos III, FCAECC and co-financed by FEDER (ERANET-TRANSCAN-2 iMMunocell AC17/00101); the Spanish Ministry of Science and Innovation and co-financed by FSE (Torres Quevedo fellowship, PTQ-16-08623); the Black Swan Research Initiative of the International Myeloma Foundation; European Research Council (ERC) under the European Commission’s H2020 Framework Programme (MYELOMANEXT, 680200); the Qatar National Research Fund (QNRF) Award No. 7-916-3-237; the AACR-Millennium Fellowship in Multiple Myeloma Research (15-40-38-PAIV); the Leukemia Research Foundation; and the Multiple Myeloma Research Foundation (MMRF) under the 2019 Research Fellowship Award.

Purpose: Germ-line mutations in the exonuclease domains of POLE and POLD1 have been recently associated with polyposis and colorectal cancer (CRC) predisposition. Here, we aimed to gain a better understanding of the phenotypic characteristics of this syndrome to establish specific criteria for POLE and POLD1 mutation screening and to help define the clinical management of mutation carriers. Genet Med 18 4, 325–332. Methods: The exonuclease domains of POLE and POLD1 were studied in 529 kindred, 441 with familial nonpolyposis CRC and 88 with polyposis, by using pooled DNA amplification and massively parallel sequencing. Genet Med 18 4, 325–332. Results: Seven novel or rare genetic variants were identified. In addition to the POLE p.L424V recurrent mutation in a patient with polyposis, CRC and oligodendroglioma, six novel or rare POLD1 variants (four of them, p.D316H, p.D316G, p.R409W, and p.L474P, with strong evidence for pathogenicity) were identified in nonpolyposis CRC families. Phenotypic data from these and previously reported POLE/POLD1 carriers point to an associated phenotype characterized by attenuated or oligo-adenomatous colorectal polyposis, CRC, and probably brain tumors. In addition, POLD1 mutations predispose to endometrial and breast tumors. Genet Med 18 4, 325–332. Conclusion: Our results widen the phenotypic spectrum of the POLE/POLD1-associated syndrome and identify novel pathogenic variants. We propose guidelines for genetic testing and surveillance recommendations. Genet Med 18 4, 325–332.

To the editor: Essential thrombocythemia (ET), polycythemia vera, and primary myelofibrosis constitute a group of hematological disorders classically identified as BCR-ABL –negative myeloproliferative neoplasms (MPNs).[1][1],[2][2] Our understanding of the etiology of MPNs has benefited from the

Background: Genetic characterization is becoming relevant to predict risk of progression in smoldering MM and is fundamental to estimate survival in active MM. Thus, patients undergo multiple bone marrow (BM) aspirates for genetic screening that beyond painful, may not be fully representative due to patchy BM involvement, spatial genomic heterogeneity, or extramedullary disease. Accordingly, cell-free DNA has been investigated and showed high concordance with BM aspirates, but information is typically restricted to a few recurrent mutations since comprehensive genetic characterization (eg. whole-exome sequencing, WES) is applicable to Aim: To compare the genetic landscape of CTCs vs matched BM clonal plasma cells (PCs) and extramedullary (EM) plasmacytomas, and validate standardized assays for CTCs' detection, isolation and genetic characterization. Methods: We used EuroFlow next-generation flow (NGF) cytometry to detect and isolate peripheral blood (PB) CTCs and matched BM clonal PCs from 38 MM patients (25 at diagnosis and 13 at relapse). In 8 cases, clonal PCs from EM plasmacytomas were also FACSorted. PB T cells were always used as matched germline control. In the training set, we performed custom WES (preceded by triplicates of whole-genome amplification) in matched CTCs, BM and EM clonal PCs from the 8 patients with all three spatially distributed clones. Only those mutations present in 2/3 libraries analyzed per sample were considered positive. In the validation set, we compared mutations, copy number alterations (CNA) and translocations present in CTCs and BM clonal PCs using the Chromium Exome Solution for low DNA-input (n=8), and solely CNA using the Affymetrix CytoScan HD platform (n=22). Read mapping, variant and structural calling were performed with the Multisample Exome (Dreamgenics) and LongRanger (10XGenomics) pipelines. The Chromosome Analysis Suite software (Affymetrix) was used to analyze CNA. Only those mutations with ≥10% variant allele frequency (VAF) and CNA larger than 1Mb were considered. Results: In the training set, 193/226 (85%) and 231/269 (86%) of total mutations present in BM and EM clonal PCs, respectively, were detectable on CTCs. All MM recurrent mutations (eg. BRAF) found in BM or EM clonal PCs were present in CTCs. Of note, there were 39 mutations in EM plasmacytomas that were detectable in CTCs but absent in BM clonal PCs. Furthermore, up to 50 mutations were present in CTCs while undetectable in BM clonal PCs (n=44) or EM plasmacytomas (n=6). After showing that CTCs harbor most mutations present in both medullary and extramedullary disease and even unveil mutations undetectable in single BM aspirates or individual EM plasmacytomas, we sought to evaluate the performance of standardized assays suitable to screen mutations and/or CNA from low cell numbers (ie. CTCs). Using 10XGenomics, 250/266 (94%) of total mutations and 17/17 (100%) of MM recurrent mutations present in BM clonal PCs were detectable on CTCs (eg. KRAS, BRAF, TP53 or FAM46C). The VAF of private mutations ranged between 0.1 and 0.3, suggesting these were subclonal in their respective spatial regions. Using 10XGenomics, 101/119 (85%) CNA and 2/2 (100%) IgH Tx present in BM clonal PCs were detectable in CTCs. Using the Cytoscan HD, there was 100% concordance between CNA in CTCs and BM clonal PCs, both at the chromosomal arm and interstitial levels. All mutations in TP53 were detectable in CTCs. Furthermore, +1q, del(1p), del(17p) or t(4;14) were always detected in CTCs whenever present in BM clonal PCs, and confirmed by FISH. Conversely, such comprehensive genetic characterization unveiled innumerous CNA and translocations not tested by routine FISH panels [eg. MYC amplification or t(6;14)]. Conclusions: Using two different standardized methods, we showed in the largest series in which CTCs were genetically characterized, that these are a reliable surrogate of MM patients' genetic landscape inside and outside the BM. Because NGF is broadly used, quantification, isolation and genetic characterization of CTCs may emerge as an optimal and standardized approach for non-invasive risk-stratification of MM patients. Disclosures Rios: Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. San-Miguel:Amgen, Bristol-Myers Squibb, Celgene, Janssen, MSD, Novartis, Roche, Sanofi, and Takeda: Consultancy, Honoraria. Paiva:Amgen, Bristol-Myers Squibb, Celgene, Janssen, Merck, Novartis, Roche and Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene, Janssen, Sanofi and Takeda: Consultancy.

Mantle cell lymphoma (MCL) is an aggressive tumor, but a subset of patients may follow an indolent clinical course. To understand the mechanisms underlying this biological heterogeneity, we performed whole-genome and/or whole-exome sequencing on 29 MCL cases and their respective matched normal DNA, as well as 6 MCL cell lines. Recurrently mutated genes were investigated by targeted sequencing in an independent cohort of 172 MCL patients. We identified 25 significantly mutated genes, including known drivers such as ataxia-telangectasia mutated (ATM), cyclin D1 (CCND1), and the tumor suppressor TP53; mutated genes encoding the anti-apoptotic protein BIRC3 and Toll-like receptor 2 (TLR2); and the chromatin modifiers WHSC1, MLL2, and MEF2B. We also found NOTCH2 mutations as an alternative phenomenon to NOTCH1 mutations in aggressive tumors with a dismal prognosis. Analysis of two simultaneous or subsequent MCL samples by whole-genome/whole-exome (n = 8) or targeted (n = 19) sequencing revealed subclonal heterogeneity at diagnosis in samples from different topographic sites and modulation of the initial mutational profile at the progression of the disease. Some mutations were predominantly clonal or subclonal, indicating an early or late event in tumor evolution, respectively. Our study identifies molecular mechanisms contributing to MCL pathogenesis and offers potential targets for therapeutic intervention.

International audience; Background Progeroid syndromes are genetic disorders that recapitulate some phenotypes of physiological ageing. Classical progerias, such as Hutchinson-Gilford progeria syndrome (HGPS), are generally caused by mutations in LMNA leading to accumulation of the toxic protein progerin and consequently, to nuclear envelope alterations. In this work, we describe a novel phenotypic feature of the progeria spectrum affecting three unrelated newborns and identify its genetic cause. Methods and results Patients reported herein present an extremely homogeneous phenotype that somewhat recapitulates those of patients with HGPS and mandibuloacral dysplasia. However, pathological signs appear earlier, are more aggressive and present distinctive features including episodes of severe upper airway obstruction. Exome and Sanger sequencing allowed the identification of heterozygous de novo c.163G>A, p.E55K and c.164A>G, p.E55G mutations in LMNA as the alterations responsible for this disorder. Functional analyses demonstrated that fibroblasts from these patients suffer important dysfunctions in nuclear lamina, which generate profound nuclear envelope abnormalities but without progerin accumulation. These nuclear alterations found in patients' dermal fibroblasts were also induced by ectopic expression of the corresponding site-specific LMNA mutants in control human fibroblasts. Conclusions Our results demonstrate the causal role of p.E55K and p.E55G lamin A mutations in a disorder which manifests novel phenotypic features of the progeria spectrum characterised by neonatal presentation and aggressive clinical evolution, despite being caused by lamin A/C missense mutations with effective prelamin A processing.

Are kallikreins (KLKs), the whey-acidic-protein four-disulfide core domain (WFDCs) and their neighbors, semenogelins (SEMGs), known to play a role in the cascade of semen coagulation and liquefaction, associated with male infertility?Several KLK and SEMG variants are overrepresented among hyperviscosity, asthenozoospermia and oligozoospermia, supporting an effect of abnormal semen liquefaction on the loss of semen quality and in lowering male reproductive fitness.In the cascade of semen coagulation and liquefaction the spermatozoa coated by EPPIN (a protease inhibitor of the WFDC family) are entrapped in a cross-linked matrix established by SEMGs. After ejaculation, the SEMG matrix is hydrolyzed by KLK3/2 in a fine-tuned process regulated by other KLKs that allows the spermatozoa to increase motility.This study includes a cohort of 238 infertility-related cases and 91 controls with normal spermiogram analysis. The remaining 126 controls are healthy males with unknown semen parameters. Sample collection was carried out from June 2011 to January 2015 and variant screening from May 2013 to August 2015.We performed a screening by massive parallel sequencing in a pooled sample (N = 222) covering approximately 93 kb of KLK (19q13.3-13.4) and WFDC (20q13) clusters, followed by the genotyping of most promising variants in the full cohort.Overall, 160 common and 296 low-frequency variants passed the quality control filtering. Statistical tests disclosed an association with hyperviscosity of a KLK7 regulatory variant (P = 0.0035), and unveiled a higher burden of deleterious mutations in KLKs than expected by chance (P = 0.0106). KLK variants found to be overrepresented in cases included two substitutions likely affecting the substrate binding pocket, two nonsynonymous variants overlapping in the three-dimensional structure and two mutations mapping in consecutive N-terminal residues. Other variants identified in SEMGs possibly contributing to hyperviscosity and asthenozoospermia consisted of three replacements predicted to modify targets of proteolysis (P = 0.0442 for SEMG1 p.Gly400Asp) and a copy number variation associated with a reduced risk of oligozoospermia (P = 0.0293).Not applicable.The sampling of a few hundred individuals has limited power to detected associations with low-frequency variants and only a small set of variants was prioritized for genotyping. Other susceptibility variants for male infertility may remain unidentified.We provide important evidence for an effect of KLKs and SEMGs variability on semen quality and for modifications in the process of semen liquefaction as a possible cause for male infertility.This work was funded through the Portuguese Foundation for Science and Technology (FCT) and FEDER through COMPETE and QREN. The authors have no conflict of interest to declare.

Chronic lymphocytic leukaemia (CLL) is a frequent disease in which the genetic alterations determining the clinicobiological behaviour are not fully understood. Here we describe a comprehensive evaluation of the genomic landscape of 452 CLL cases and 54 patients with monoclonal B-lymphocytosis, a precursor disorder. We extend the number of CLL driver alterations, including changes in ZNF292, ZMYM3, ARID1A and PTPN11. We also identify novel recurrent mutations in non-coding regions, including the 3′ region of NOTCH1, which cause aberrant splicing events, increase NOTCH1 activity and result in a more aggressive disease. In addition, mutations in an enhancer located on chromosome 9p13 result in reduced expression of the B-cell-specific transcription factor PAX5. The accumulative number of driver alterations (0 to ≥ 4) discriminated between patients with differences in clinical behaviour. This study provides an integrated portrait of the CLL genomic landscape, identifies new recurrent driver mutations of the disease, and suggests clinical interventions that may improve the management of this neoplasia., This work was funded by Spanish Ministry of Economy and Competitiveness through the Instituto de Salud Carlos III (ISCIII) and Red Temática de Investigación del Cáncer (RTICC). C.L.-O. is an Investigator of the Botin Foundation supported by Banco Santander through its Santander Universities Global Division, and E.Ca. and D.T. are Institució Catalana de Recerca i Estudis Avançats-Academia investigators. We acknowledge Partnership for Advanced Computing in Europe (PRACE) for awarding us access to resource Marenostrum based in Spain at the BSC, the Pershing Square Sohn Cancer Research Alliance and European Union’s FP7 through the Blueprint Consortium.

This work was supported by grants from Ministerio de Economía y Competitividad-Spain and Red Temática de Investigación del Cáncer (RTICC)., This work was supported by grants from Ministerio de Economía y Competitividad-Spain and Red Temática de Investigación del Cáncer (RTICC). C.L-O. is an Investigator of the Botín Foundation. V.Q. is a Ramón y Cajal Investigator with the Consolider-Ingenio RNAREG Consortium. The Instituto Universitario de Oncología is supported by Obra Social Cajastur and Instituto de Salud Carlos III (RTICC)., Bárcena, C., Quesada, V., De Sandre-Giovannoli, A., Puente, D.A., Fernández-Toral, J., Sigaudy, S., Baban, A., Lévy, N., Velasco, G., López-Otín, C.

Mutations in different genes encoding sarcomeric proteins are responsible for 50-60% of familial cases of hypertrophic cardiomyopathy (HCM); however, the genetic alterations causing the disease in one-third of patients are currently unknown. Here we describe a case with familial HCM of unknown cause. Whole-exome sequencing reveals a variant in the gene encoding the sarcomeric protein filamin C (p.A1539T) that segregates with the disease in this family. Sequencing of 92 HCM cases identifies seven additional variants segregating with the disease in eight families. Patients with FLNC mutations show marked sarcomeric abnormalities in cardiac muscle, and functional analysis reveals that expression of these FLNC variants resulted in the formation of large filamin C aggregates. Clinical studies indicate that FLNC-mutated patients have higher incidence of sudden cardiac death. On the basis of these findings, we conclude that mutations in the gene encoding the sarcomeric protein filamin C cause a new form of familial HMC.

EM disease in MM increases from newly-diagnosed into relapsed patients, and typically predicts for inferior survival. In fact, no treatment seems to be effective in cases with plasma cell (PC) leukemia, which represents the most aggressive form of EM MM. Unfortunately, the mechanisms of extramedullary spread in MM are not well understood, and there is almost no data about the genetic landscape of both forms of EMD (plasmacytomas and peripheral blood CTCs). Here, we performed whole exome sequencing (WES) to analyze the genomic profiles of highly purified FACS sorted BM and EM clonal PCs from 6 patients with relapsed MM. In 5/6 cases we had all three tissue specific clones, whereas in the remaining case no CTCs were detectable. Depending on the amount of genomic DNA from each clone, whole-genome amplification was performed and in such cases, triplicates of 10 ng of DNA were amplified up to 10 µg using the Illustra GenomiPhi HY DNA amplification kit (GE healthcare). Enrichment of exonic sequences was performed for each library using the SureSelectXT Human All Exon V5+UTRs capture kit (Agilent). To identify somatic mutations we used the mutation caller named Varscan. Variants potentially affecting protein function, including non-synonymous variants, frameshifts in the coding sequence, stop codon-introducing (nonsense) or variants potentially affecting splicing, were analyzed. Only those mutations present in 2/3 libraries analyzed per sample were considered positive. Overall, a median of 89 (67 - 474) somatic mutations were detected. EM plasmacytomas showed the highest mutation load, followed by CTCs and BM clonal PCs (85 vs 77 vs 75, respectively; P=.07), supporting a higher genomic instability/evolution of EM clones. Strikingly, all 6 cases showed lack of concordance in the mutation profiles of the three tissue related clones; even 2x2 comparisons between BM clonal PCs vs CTCs or plasmacytomas, or between the two forms of EM MM (ie. plasmacytomas vs CTCs) showed lack of 100% concordance in every single patient. Despite high inter-tissue heterogeneity, it should be noted that whenever present, recurrent and potentially actionable mutations in genes such as KRAS (n=3), KDM4A (n=2), KMT2A (n=2), ARID5B (n=2), TRIO (n=2), BRAF (n=1) or CCND1 (n=1) were detected in all three clones, with the exception of one patient in which CTCs lacked a KRAS mutation. Only one and less frequent actionable mutation in the EPHB2 gene (eg. Herceptin) was exclusively noted in the EM plasmacytoma from one patient. In order to understand the cellular origin of the three tissue related subclones, we then investigated the degree of similarity between each pair of clones at the individual patient level. The pair of clones showing the highest similarity in their mutation profiles were EM plasmacytomas with CTCs (60%, 30% - 94%), followed by BM clonal PCs with CTCs (58%, 35% - 92%), and by BM clonal PCs with EM plasmacytomas (57%, 37% - 91%). Thus, these data suggests that while CTC clones may represent a cellular bridge in between BM and EM plasmacytomas, there is continuous genomic evolution once the different clones have seeded in their respective tissue niches. Accordingly, EM plasmacytomas showed the highest number of specific mutations, followed by BM clonal PCs and CTCs (medians of 9, 4 and 3, respective). We then looked for recurrent mutations specifically present in EM clones, and found that CTCs showed exclusive and recurrent mutations in the CEP152, FSIP2, SYNE1 and TENM1 and ZNF585A genes, whereas EM plasmacytomas showed exclusive and recurrent mutations in the PITRM1 (Metalloprotease 1) gene. Furthermore, ATP7B, MTOR, TBC1D21 and ZNF717 mutations were present in both CTCs and plasmacytomas. In summary, we compared for the first time the genomic profiles of BM vs EM CTCs and plasmacytoma clones, and showed at the individual patient level, the existence of high mutation heterogeneity in between all three tissue related clones. However, actionable mutations in genes such as KRAS or BRAF were typically shared by BM and EM clones. According to the level of similarity between each clone, CTCs would be the most plausible precursor of EM plasmacytomas. Nevertheless, based on the number of specific mutations present in EM clones, it is likely that EM spreading followed by continuous clonal evolution starts much earlier prior to its clinical detection, which emphasizes the need for sensitive techniques to capture the early stages of EM spreading. Disclosures Paiva: Celgene: Honoraria, Research Funding; Janssen: Honoraria; Takeda: Honoraria, Research Funding; Sanofi: Consultancy, Research Funding; EngMab: Research Funding; Amgen: Honoraria; Binding Site: Research Funding.

Here we perform whole-exome sequencing of samples from 105 individuals with chronic lymphocytic leukemia (CLL), the most frequent leukemia in adults in Western countries. We found 1,246 somatic mutations potentially affecting gene function and identified 78 genes with predicted functional alterations in more than one tumor sample. Among these genes, SF3B1, encoding a subunit of the spliceosomal U2 small nuclear ribonucleoprotein (snRNP), is somatically mutated in 9.7% of affected individuals. Further analysis in 279 individuals with CLL showed that SF3B1 mutations were associated with faster disease progression and poor overall survival. This work provides the first comprehensive catalog of somatic mutations in CLL with relevant clinical correlates and defines a large set of new genes that may drive the development of this common form of leukemia. The results reinforce the idea that targeting several well-known genetic pathways, including mRNA splicing, could be useful in the treatment of CLL and other malignancies.

This paper is distributed under the terms of the Creative Commons Attribution-Non-Commercial-Share Alike licence.-- et al., Chronic lymphocytic leukaemia (CLL), the most frequent leukaemia in adults in Western countries, is a heterogeneous disease with variable clinical presentation and evolution(1,2). Two major molecular subtypes can be distinguished, characterized respectively by a high or low number of somatic hypermutations in the variable region of immunoglobulin genes(3,4). The molecular changes leading to the pathogenesis of the disease are still poorly understood. Here we performed whole-genome sequencing of four cases of CLL and identified 46 somatic mutations that potentially affect gene function. Further analysis of these mutations in 363 patients with CLL identified four genes that are recurrently mutated: notch 1 (NOTCH1), exportin 1 (XPO1), myeloid differentiation primary response gene 88 (MYD88) and kelch-like 6 (KLHL6). Mutations in MYD88 and KLHL6 are predominant in cases of CLL with mutated immunoglobulin genes, whereas NOTCH1 and XPO1 mutations are mainly detected in patients with unmutated immunoglobulins. The patterns of somatic mutation, supported by functional and clinical analyses, strongly indicate that the recurrent NOTCH1, MYD88 and XPO1 mutations are oncogenic changes that contribute to the clinical evolution of the disease. To our knowledge, this is the first comprehensive analysis of CLL combining whole-genome sequencing with clinical characteristics and clinical outcomes. It highlights the usefulness of this approach for the identification of clinically relevant mutations in cancer., This work was funded by the Spanish Ministry of Science and Innovation (MICINN) through the Instituto de Salud Carlos III (ISCIII) and Red Temática de Investigación del Cáncer (RTICC) del ISCIII. C.L.-O. is an Investigator of the Botin Foundation and D.T., of the ICREA program. We thank E. Santos for his support of this project, A. Carracedo and J. Benítez for genotyping studies, C. Fortuny for the supply of samples and N. Villahoz and M. C. Muro for their work in the coordination of the CLL-ICGC Consortium.