@article {10745, title = {Loss-of-function mutations in cause a new form of inherited thrombocytopenia.}, journal = {Blood}, volume = {133}, year = {2019}, month = {2019 Mar 21}, pages = {1346-1357}, abstract = {

Inherited thrombocytopenias (ITs) are a heterogeneous group of disorders characterized by low platelet count that may result in bleeding tendency. Despite progress being made in defining the genetic causes of ITs, nearly 50\% of patients with familial thrombocytopenia are affected with forms of unknown origin. Here, through exome sequencing of 2 siblings with autosomal-recessive thrombocytopenia, we identified biallelic loss-of-function variants in This gene encodes for a receptor-like PTP, PTPRJ (or CD148), which is expressed abundantly in platelets and megakaryocytes. Consistent with the predicted effects of the variants, both probands have an almost complete loss of PTPRJ at the messenger RNA and protein levels. To investigate the pathogenic role of PTPRJ deficiency in hematopoiesis in vivo, we carried out CRISPR/Cas9-mediated ablation of (the ortholog of human ) in zebrafish, which induced a significantly decreased number of CD41 thrombocytes in vivo. Moreover, megakaryocytes of our patients showed impaired maturation and profound defects in SDF1-driven migration and formation of proplatelets in vitro. Silencing of in a human megakaryocytic cell line reproduced the functional defects observed in patients{\textquoteright} megakaryocytes. The disorder caused by mutations presented as a nonsyndromic thrombocytopenia characterized by spontaneous bleeding, small-sized platelets, and impaired platelet responses to the GPVI agonists collagen and convulxin. These platelet functional defects could be attributed to reduced activation of Src family kinases. Taken together, our data identify a new form of IT and highlight a hitherto unknown fundamental role for PTPRJ in platelet biogenesis.

}, issn = {1528-0020}, doi = {10.1182/blood-2018-07-859496}, author = {Marconi, Caterina and Di Buduo, Christian A and LeVine, Kellie and Barozzi, Serena and Faleschini, Michela and Bozzi, Valeria and Palombo, Flavia and McKinstry, Spencer and Lassandro, Giuseppe and Giordano, Paola and Noris, Patrizia and Balduini, Carlo L and Savoia, Anna and Balduini, Alessandra and Pippucci, Tommaso and Seri, Marco and Katsanis, Nicholas and Pecci, Alessandro} } @article {10820, title = {MYH9-Related Thrombocytopenia: Four Novel Variants Affecting the Tail Domain of the Non-Muscle Myosin Heavy Chain IIA Associated with a Mild Clinical Evolution of the Disorder.}, journal = {Hamostaseologie}, volume = {39}, year = {2019}, month = {2019 Feb}, pages = {87-94}, abstract = {

-related disease (-RD) is an autosomal-dominant thrombocytopenia caused by mutations in the gene for non-muscle myosin heavy chain IIA (NMMHC-IIA). Patients present congenital macrothrombocytopenia and inclusions of NMMHC-IIA in leukocytes, and have a variable risk of developing kidney damage, sensorineural deafness, presenile cataracts and/or liver enzymes abnormalities. The spectrum of mutations found in -RD patients is limited and the incidence and severity of the non-congenital features are predicted by the causative variant. In particular, different alterations of the C-terminal tail domain of NMMHC-IIA associate with remarkably different disease evolution. We report four novel mutations affecting the tail domain of NMMHC-IIA and responsible for -RD in four families. Two variants cause amino acid substitutions in the coiled-coil region of NMMHC-IIA, while the other two are a splicing variant and a single nucleotide deletion both resulting in frameshift alterations of the short non-helical tailpiece. Characterization of phenotypes of affected individuals shows that all of these novel variants are associated with a mild clinical evolution of the disease.

}, issn = {2567-5761}, doi = {10.1055/s-0038-1645840}, author = {Zaninetti, Carlo and De Rocco, Daniela and Giangregorio, Tania and Bozzi, Valeria and Demeter, Judit and Leoni, Pietro and Noris, Patrizia and Ryh{\"a}nen, Samppa and Barozzi, Serena and Pecci, Alessandro and Savoia, Anna} } @article {8503, title = {Clinical and pathogenetic features of ETV6 related thrombocytopenia with predisposition to acute lymphoblastic leukemia.}, journal = {Haematologica}, year = {2016}, month = {2016 Jun 30}, abstract = {

ETV6-related thrombocytopenia (ETV6-RT) is an autosomal dominant thrombocytopenia that has been recently identified in a few families and has been suspected to predispose to hematological malignancies. To gain further information on this disorder, we searched for ETV6 mutations in the 130 families with inherited thrombocytopenia of unknown origin from our cohort of 274 consecutive pedigrees with familial thrombocytopenia. We identified 20 ETV6-RT patients from 7 pedigrees. They have 5 different ETV6 variants, including three novel mutations affecting the highly conserved E26 transformation-specific domain. The relative frequency of ETV6-RT resulted 2.6\% in the whole case series and 4.6\% among the families with known forms of inherited thrombocytopenia. The degree of thrombocytopenia and bleeding tendency of ETV6-RT patients were mild, but 4 subjects developed B-cell acute lymphoblastic leukemia during childhood, resulting in a significantly increased incidence compared to the general population. Clinical and laboratory findings did not identify any peculiar defects that can be used to suspect this disorder by routine diagnostic workup. However, at variance with most inherited thrombocytopenias, platelet size was not enlarged. In vitro studies revealed that patients megakaryocytes have defective maturation and impaired proplatelet formation. Moreover, ETV6-RT platelets have reduced ability to spread on fibrinogen. Since also the dominant thrombocytopenias due to mutations in RUNX1 and ANKRD26 are characterized by normal platelet size and predispose to hematological malignancies, we suggest that mutation screening of ETV6, RUNX1 and ANKRD26 should be performed in all the subjects with autosomal dominant thrombocytopenia and normal platelet size.

}, issn = {1592-8721}, doi = {10.3324/haematol.2016.147496}, author = {Melazzini, Federica and Palombo, Flavia and Balduini, Alessandra and De Rocco, Daniela and Marconi, Caterina and Noris, Patrizia and Gnan, Chiara and Pippucci, Tommaso and Bozzi, Valeria and Faleschini, Michela and Barozzi, Serena and Doubek, Michael and Di Buduo, Christian A and Stano Kozubik, Katerina and Radova, Lenka and Loffredo, Giuseppe and Pospisilova, Sarka and Alfano, Caterina and Seri, Marco and Balduini, Carlo L and Pecci, Alessandro and Savoia, Anna} } @article {3634, title = {Platelet diameters in inherited thrombocytopenias: analysis of 376 patients with all known disorders.}, journal = {Blood}, volume = {124}, year = {2014}, month = {2014 Aug 7}, pages = {e4-e10}, abstract = {

Abnormalities of platelet size are one of the distinguishing features of inherited thrombocytopenias (ITs), and evaluation of blood films is recommended as an essential step for differential diagnosis of these disorders. Nevertheless, what we presently know about this subject is derived mainly from anecdotal evidence. To improve knowledge in this field, we evaluated platelet size on blood films obtained from 376 patients with all 19 forms of IT identified so far and found that these conditions differ not only in mean platelet diameter, but also in platelet diameter distribution width and the percentage of platelets with increased or reduced diameters. On the basis of these findings, we propose a new classification of ITs according to platelet size. It distinguishes forms with giant platelets, with large platelets, with normal or slightly increased platelet size, and with normal or slightly decreased platelet size. We also measured platelet diameters in 87 patients with immune thrombocytopenia and identified cutoff values for mean platelet diameter and the percentage of platelets with increased or reduced size that have good diagnostic accuracy in differentiating ITs with giant platelets and with normal or slightly decreased platelet size from immune thrombocytopenia and all other forms of IT.

}, keywords = {Adolescent, Adult, Blood Platelets, Case-Control Studies, Cell Size, Child, Child, Preschool, Diagnosis, Differential, Female, Hearing Loss, Sensorineural, Humans, Infant, Male, Middle Aged, Molecular Motor Proteins, Mutation, Myosin Heavy Chains, Purpura, Thrombocytopenic, Idiopathic, Thrombocytopenia, Young Adult}, issn = {1528-0020}, doi = {10.1182/blood-2014-03-564328}, author = {Noris, Patrizia and Biino, Ginevra and Pecci, Alessandro and Civaschi, Elisa and Savoia, Anna and Seri, Marco and Melazzini, Federica and Loffredo, Giuseppe and Russo, Giovanna and Bozzi, Valeria and Notarangelo, Lucia Dora and Gresele, Paolo and Heller, Paula G and Pujol-Moix, N{\'u}ria and Kunishima, Shinji and Cattaneo, Marco and Bussel, James and De Candia, Erica and Cagioni, Claudia and Ramenghi, Ugo and Barozzi, Serena and Fabris, Fabrizio and Balduini, Carlo L} } @article {1993, title = {MYH9-related disease: five novel mutations expanding the spectrum of causative mutations and confirming genotype/phenotype correlations.}, journal = {Eur J Med Genet}, volume = {56}, year = {2013}, month = {2013 Jan}, pages = {7-12}, abstract = {

MYH9-related disease (MYH9-RD) is a rare autosomal dominant syndromic disorder caused by mutations in MYH9, the gene encoding for the heavy chain of non-muscle myosin IIA (myosin-9). MYH9-RD is characterized by congenital macrothrombocytopenia and typical inclusion bodies in neutrophils associated with a variable risk of developing sensorineural deafness, presenile cataract, and/or progressive nephropathy. The spectrum of mutations responsible for MYH9-RD is limited. We report five families, each with a novel MYH9 mutation. Two mutations, p.Val34Gly and p.Arg702Ser, affect the motor domain of myosin-9, whereas the other three, p.Met847_Glu853dup, p.Lys1048_Glu1054del, and p.Asp1447Tyr, hit the coiled-coil tail domain of the protein. The motor domain mutations were associated with more severe clinical phenotypes than those in the tail domain.

}, keywords = {Adolescent, Adult, Amino Acid Sequence, Amino Acid Substitution, Base Sequence, Child, Child, Preschool, Exons, Female, Genes, Dominant, Genetic Association Studies, Humans, Male, Middle Aged, Models, Molecular, Molecular Motor Proteins, Molecular Sequence Data, Mutation, Myosin Heavy Chains, Pedigree, Protein Conformation, Sequence Alignment, Syndrome, Thrombocytopenia, Young Adult}, issn = {1878-0849}, doi = {10.1016/j.ejmg.2012.10.009}, author = {De Rocco, Daniela and Zieger, Barbara and Platokouki, Helen and Heller, Paula G and Pastore, Annalisa and Bottega, Roberta and Noris, Patrizia and Barozzi, Serena and Glembotsky, Ana C and Pergantou, Helen and Balduini, Carlo L and Savoia, Anna and Pecci, Alessandro} } @article {1920, title = {MYH9-related disorders: report on a patient of Greek origin presenting with macroscopic hematuria and presenile cataract, caused by an R1165C mutation.}, journal = {J Pediatr Hematol Oncol}, volume = {34}, year = {2012}, month = {2012 Aug}, pages = {412-5}, abstract = {

Myosin heavy chain-9 (MYH9)-related disorders represent a heterogenous group of hereditary diseases caused by mutations in the gene encoding the heavy chain of nonmuscle myosin IIA. May-Hegglin anomaly and Fechtner, Sebastian, and Epstein syndromes are the four phenotypes of the disease, characterized by congenital macrothrombocytopenia and distinguished by different combinations of clinical signs that may include glomerulonephritis, sensorineural hearing loss, and presenile cataract. The spectrum of mutations responsible for the disease is wide and the existence of genotype-phenotype correlation remains a critical issue. We report the first case of an MYH9-RD in a patient of Greek origin presenting with macroscopic hematuria and presenile cataract caused by a p.R1165C mutation. The same mutation was present in the patient{\textquoteright}s father, who exhibited no extrahematological features of the disease. The p.R1165C mutation is one of the MYH9 alterations whose prognostic significance is still poorly defined. Thus, the patients described add to the limited existing data on the MYH9 mutations and their resultant phenotypes.

}, keywords = {Adolescent, Cataract, Diagnosis, Differential, DNA Mutational Analysis, Greece, Hematuria, Humans, Male, Molecular Motor Proteins, Myosin Heavy Chains, Point Mutation}, issn = {1536-3678}, doi = {10.1097/MPH.0b013e318257a64b}, author = {Economou, Marina and Batzios, Spyros P and Pecci, Alessandro and Printza, Nikoletta and Savoia, Anna and Barozzi, Serena and Theodoridou, Stamatia and Teli, Aikaterini and Psillas, Georgios and Zafeiriou, Dimitrios I} } @article {1688, title = {Mutations in the 5{\textquoteright} UTR of ANKRD26, the ankirin repeat domain 26 gene, cause an autosomal-dominant form of inherited thrombocytopenia, THC2.}, journal = {Am J Hum Genet}, volume = {88}, year = {2011}, month = {2011 Jan 7}, pages = {115-20}, abstract = {

THC2, an autosomal-dominant thrombocytopenia described so far in only two families, has been ascribed to mutations in MASTL or ACBD5. Here, we show that ANKRD26, another gene within the THC2 locus, and neither MASTL nor ACBD5, is mutated in eight unrelated families. ANKRD26 was also found to be mutated in the family previously reported to have an ACBD5 mutation. We identified six different ANKRD26 mutations, which were clustered in a highly conserved 19~bp sequence located in the 5{\textquoteright} untranslated region. Mutations were not detected in 500 controls and are absent from the 1000 Genomes database. Available data from an animal model and Dr.~Watson{\textquoteright}s genome give evidence against haploinsufficiency as the pathogenetic mechanism for ANKRD26-mediated thrombocytopenia. The luciferase reporter assay suggests that these 5{\textquoteright} UTR mutations might enhance ANKRD26 expression. ANKRD26 is the ancestor of a family of primate-specific genes termed POTE, which have been recently identified as a family of proapoptotic proteins. Dysregulation of apoptosis might therefore be the pathogenetic mechanism, as demonstrated for another thrombocytopenia, THC4. Further investigation is needed to provide evidence supporting this hypothesis.

}, keywords = {Ankyrin Repeat, Base Sequence, Chromosome Breakage, Chromosome Disorders, Conserved Sequence, Female, Genes, Dominant, Genetic Loci, Haploinsufficiency, Humans, Male, Molecular Sequence Data, Mutation, Pedigree, Thrombocytopenia}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2010.12.006}, author = {Pippucci, Tommaso and Savoia, Anna and Perrotta, Silverio and Pujol-Moix, N{\'u}ria and Noris, Patrizia and Castegnaro, Giovanni and Pecci, Alessandro and Gnan, Chiara and Punzo, Francesca and Marconi, Caterina and Gherardi, Samuele and Loffredo, Giuseppe and De Rocco, Daniela and Scianguetta, Saverio and Barozzi, Serena and Magini, Pamela and Bozzi, Valeria and Dezzani, Luca and Di Stazio, Mariateresa and Ferraro, Marcella and Perini, Giovanni and Seri, Marco and Balduini, Carlo L} }