TY - JOUR T1 - ACTN1 mutations lead to a benign form of platelet macrocytosis not always associated with thrombocytopenia. JF - Br J Haematol Y1 - 2018 A1 - Faleschini, Michela A1 - Melazzini, Federica A1 - Marconi, Caterina A1 - Giangregorio, Tania A1 - Pippucci, Tommaso A1 - Cigalini, Elena A1 - Pecci, Alessandro A1 - Bottega, Roberta A1 - Ramenghi, Ugo A1 - Siitonen, Timo A1 - Seri, Marco A1 - Pastore, Annalisa A1 - Savoia, Anna A1 - Noris, Patrizia AB -

The inherited thrombocytopenias (IT) are a heterogeneous group of diseases resulting from mutations in more than 30 different genes. Among them, ACTN1-related thrombocytopenia (ACTN1-RT; Online Mendelian Inheritance in Man: 615193) is one of the most recently identified forms. It has been described as a mild autosomal dominant macrothrombocytopenia caused by mutations in ACTN1, a gene encoding for one of the two non-muscle isoforms of α-actinin. We recently identified seven new unrelated families with ACTN1-RT caused by different mutations. Two of them are novel missense variants (p.Trp128Cys and p.Pro233Leu), whose pathogenic role has been confirmed by in vitro studies. Together with the 10 families we have previously described, our cohort of ACTN1-RT now consists of 49 individuals carrying ACTN1 mutations. This is the largest case series ever collected and enabled a critical evaluation of the clinical aspects of the disease. We concluded that ACTN1-RT is the fourth most frequent form of IT worldwide and it is characterized by platelet macrocytosis in all affected subjects and mild thrombocytopenia in less than 80% of cases. The risk of bleeding, either spontaneous or upon haemostatic challenge, is negligible and there are no other associated defects, either congenital or acquired. Therefore, ACTN1-RT is a benign form of IT, whose diagnosis provides affected individuals and their families with a good prognosis.

VL - 183 IS - 2 U1 - http://www.ncbi.nlm.nih.gov/pubmed/30351444?dopt=Abstract ER - TY - JOUR T1 - Hypomorphic FANCA mutations correlate with mild mitochondrial and clinical phenotype in Fanconi anemia. JF - Haematologica Y1 - 2018 A1 - Bottega, Roberta A1 - Nicchia, Elena A1 - Cappelli, Enrico A1 - Ravera, Silvia A1 - De Rocco, Daniela A1 - Faleschini, Michela A1 - Corsolini, Fabio A1 - Pierri, Filomena A1 - Calvillo, Michaela A1 - Russo, Giovanna A1 - Casazza, Gabriella A1 - Ramenghi, Ugo A1 - Farruggia, Piero A1 - Dufour, Carlo A1 - Savoia, Anna AB -

Fanconi anemia is a rare disease characterized by congenital malformations, aplastic anemia, and predisposition to cancer. Despite the consolidated role of the Fanconi anemia proteins in DNA repair, their involvement in mitochondrial function is emerging. The purpose of this work was to assess whether the mitochondrial phenotype, independent of genomic integrity, could correlate with patient phenotype. We evaluated mitochondrial and clinical features of 11 affected individuals homozygous or compound heterozygous for p.His913Pro and p.Arg951Gln/Trp, the two residues of FANCA that are more frequently affected in our cohort of patients. Although p.His913Pro and p.Arg951Gln proteins are stably expressed in cytoplasm, they are unable to migrate in the nucleus, preventing cells from repairing DNA. In these cells, the electron transfer between respiring complex I-III is reduced and the ATP/AMP ratio is impaired with defective ATP production and AMP accumulation. These activities are intermediate between those observed in wild-type and FANCA-/- cells, suggesting that the variants at residues His913 and Arg951 are hypomorphic mutations. Consistent with these findings, the clinical phenotype of most of the patients carrying these mutations is mild. These data further support the recent finding that the Fanconi anemia proteins play a role in mitochondria, and open up possibilities for genotype/phenotype studies based on novel mitochondrial criteria.

VL - 103 IS - 3 U1 - http://www.ncbi.nlm.nih.gov/pubmed/29269525?dopt=Abstract ER - TY - JOUR T1 - Defects in mitochondrial energetic function compels Fanconi Anaemia cells to glycolytic metabolism. JF - Biochim Biophys Acta Mol Basis Dis Y1 - 2017 A1 - Cappelli, Enrico A1 - Cuccarolo, Paola A1 - Stroppiana, Giorgia A1 - Miano, Maurizio A1 - Bottega, Roberta A1 - Cossu, Vanessa A1 - Degan, Paolo A1 - Ravera, Silvia KW - Cell Line KW - Fanconi Anemia KW - Glycolysis KW - Humans KW - Mitochondria KW - Oxidative Phosphorylation KW - Oxidative Stress AB -

Energetic metabolism plays an essential role in the differentiation of haematopoietic stem cells (HSC). In Fanconi Anaemia (FA), DNA damage is accumulated during HSC differentiation, an event that is likely associated with bone marrow failure (BMF). One of the sources of the DNA damage is altered mitochondrial metabolism and an associated increment of oxidative stress. Recently, altered mitochondrial morphology and a deficit in the energetic activity in FA cells have been reported. Considering that mitochondria are the principal site of aerobic ATP production, we investigated FA metabolism in order to understand what pathways are able to compensate for this energy deficiency. In this work, we report that the impairment in mitochondrial oxidative phosphorylation (OXPHOS) in FA cells is countered by an increase in glycolytic flux. By contrast, glutaminolysis appears lower with respect to controls. Therefore, it is possible to conclude that in FA cells glycolysis represents the main pathway for producing energy, balancing the NADH/NAD ratio by the conversion of pyruvate to lactate. Finally, we show that a forced switch from glycolytic to OXPHOS metabolism increases FA cell oxidative stress. This could be the cause of the impoverishment in bone marrow HSC during exit from the homeostatic quiescent state. This is the first work that systematically explores FA energy metabolism, highlighting its flaws, and discusses the possible relationships between these defects and BMF.

VL - 1863 IS - 6 U1 - http://www.ncbi.nlm.nih.gov/pubmed/28315453?dopt=Abstract ER - TY - JOUR T1 - Gray platelet syndrome: Novel mutations of the NBEAL2 gene. JF - Am J Hematol Y1 - 2017 A1 - Bottega, Roberta A1 - Nicchia, Elena A1 - Alfano, Caterina A1 - Glembotsky, Ana C A1 - Pastore, Annalisa A1 - Bertaggia-Calderara, Debora A1 - Bisig, Bettina A1 - Duchosal, Michel A A1 - Arbesú, Guillermo A1 - Alberio, Lorenzo A1 - Heller, Paula G A1 - Savoia, Anna KW - Adult KW - Alleles KW - Blood Proteins KW - Child KW - Female KW - Gene Expression KW - Gene Frequency KW - Genotype KW - Gray Platelet Syndrome KW - Humans KW - Male KW - Mutation KW - Phenotype KW - Platelet Aggregation KW - Platelet Count KW - Platelet Membrane Glycoproteins VL - 92 IS - 2 U1 - http://www.ncbi.nlm.nih.gov/pubmed/27870194?dopt=Abstract ER - TY - JOUR T1 - Mutations of RUNX1 in families with inherited thrombocytopenia. JF - Am J Hematol Y1 - 2017 A1 - De Rocco, Daniela A1 - Melazzini, Federica A1 - Marconi, Caterina A1 - Pecci, Alessandro A1 - Bottega, Roberta A1 - Gnan, Chiara A1 - Palombo, Flavia A1 - Giordano, Paola A1 - Coccioli, Maria Susanna A1 - Glembotsky, Ana C A1 - Heller, Paula G A1 - Seri, Marco A1 - Savoia, Anna A1 - Noris, Patrizia KW - Adult KW - Blood Platelets KW - Cell Size KW - Child KW - Child, Preschool KW - Core Binding Factor Alpha 2 Subunit KW - Female KW - Frameshift Mutation KW - Genes, Dominant KW - Heterozygote KW - Humans KW - Introns KW - Leukemia, Myeloid, Acute KW - Male KW - Middle Aged KW - Mutation, Missense KW - Protein Domains KW - RNA Splice Sites KW - Sequence Deletion KW - Thrombocythemia, Essential KW - Thrombopoietin KW - Transcriptional Activation KW - Young Adult VL - 92 IS - 6 U1 - http://www.ncbi.nlm.nih.gov/pubmed/28240786?dopt=Abstract ER - TY - JOUR T1 - Evaluation of energy metabolism and calcium homeostasis in cells affected by Shwachman-Diamond syndrome. JF - Sci Rep Y1 - 2016 A1 - Ravera, Silvia A1 - Dufour, Carlo A1 - Cesaro, Simone A1 - Bottega, Roberta A1 - Faleschini, Michela A1 - Cuccarolo, Paola A1 - Corsolini, Fabio A1 - Usai, Cesare A1 - Columbaro, Marta A1 - Cipolli, Marco A1 - Savoia, Anna A1 - Degan, Paolo A1 - Cappelli, Enrico AB -

Isomorphic mutation of the SBDS gene causes Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have ribosome biogenesis and their protein synthesis altered, which are two high-energy consuming cellular processes. The reported changes in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest an energy production defect in SDS cells. In our work, we have demonstrated that SDS cells display a Complex IV activity impairment, which causes an oxidative phosphorylation metabolism defect, with a consequent decrease in ATP production. These data were confirmed by an increased glycolytic rate, which compensated for the energetic stress. Moreover, the signalling pathways involved in glycolysis activation also appeared more activated; i.e. we reported AMP-activated protein kinase hyper-phosphorylation. Notably, we also observed an increase in a mammalian target of rapamycin phosphorylation and high intracellular calcium concentration levels ([Ca(2+)]i), which probably represent new biochemical equilibrium modulation in SDS cells. Finally, the SDS cell response to leucine (Leu) was investigated, suggesting its possible use as a therapeutic adjuvant to be tested in clinical trials.

VL - 6 U1 - http://www.ncbi.nlm.nih.gov/pubmed/27146429?dopt=Abstract ER - TY - JOUR T1 - ACTN1-related thrombocytopenia: identification of novel families for phenotypic characterization. JF - Blood Y1 - 2015 A1 - Bottega, Roberta A1 - Marconi, Caterina A1 - Faleschini, Michela A1 - Baj, Gabriele A1 - Cagioni, Claudia A1 - Pecci, Alessandro A1 - Pippucci, Tommaso A1 - Ramenghi, Ugo A1 - Pardini, Simonetta A1 - Ngu, Loretta A1 - Baronci, Carlo A1 - Kunishima, Shinji A1 - Balduini, Carlo L A1 - Seri, Marco A1 - Savoia, Anna A1 - Noris, Patrizia KW - Actinin KW - Adolescent KW - Adult KW - Aged KW - Aged, 80 and over KW - Blood Platelets KW - Case-Control Studies KW - Child KW - Child, Preschool KW - Female KW - Gene Expression KW - Genotype KW - Heterozygote KW - Humans KW - Male KW - Middle Aged KW - Mutation, Missense KW - Pedigree KW - Phenotype KW - Platelet Count KW - Severity of Illness Index KW - Thrombocytopenia KW - Thrombopoiesis KW - Thrombopoietin AB -

Inherited thrombocytopenias (ITs) are a heterogeneous group of syndromic and nonsyndromic diseases caused by mutations affecting different genes. Alterations of ACTN1, the gene encoding for α-actinin 1, have recently been identified in a few families as being responsible for a mild form of IT (ACTN1-related thrombocytopenia; ACTN1-RT). To better characterize this disease, we screened ACTN1 in 128 probands and found 10 (8 novel) missense heterozygous variants in 11 families. Combining bioinformatics, segregation, and functional studies, we demonstrated that all but 1 amino acid substitution had deleterious effects. The clinical and laboratory findings of 31 affected individuals confirmed that ACTN1-RT is a mild macrothrombocytopenia with low risk for bleeding. Low reticulated platelet counts and only slightly increased serum thrombopoietin levels indicated that the latest phases of megakaryopoiesis were affected. Given its relatively high frequency in our cohort (4.2%), ACTN1-RT has to be taken into consideration in the differential diagnosis of ITs.

VL - 125 IS - 5 U1 - http://www.ncbi.nlm.nih.gov/pubmed/25361813?dopt=Abstract ER - TY - JOUR T1 - Clinical aspects of Fanconi anemia individuals with the same mutation of FANCF identified by next generation sequencing. JF - Birth Defects Res A Clin Mol Teratol Y1 - 2015 A1 - Nicchia, Elena A1 - Benedicenti, Francesco A1 - Rocco, Daniela De A1 - Greco, Chiara A1 - Bottega, Roberta A1 - Inzana, Francesca A1 - Faleschini, Michela A1 - Bonin, Serena A1 - Cappelli, Enrico A1 - Mogni, Massimo A1 - Stanzial, Franco A1 - Svahn, Johanna A1 - Dufour, Carlo A1 - Savoia, Anna AB -

BACKGROUND: Fanconi anemia (FA) is a rare genetic disease characterized by congenital malformations, aplastic anemia and increased risk of developing malignancies. FA is genetically heterogeneous as it is caused by at least 17 different genes. Among these, FANCA, FANCC, and FANCG account for approximately 85% of the patients whereas the remaining genes are mutated in only a small percentage of cases. For this reason, the molecular diagnostic process is complex and not always extended to all the FA genes, preventing the characterization of individuals belonging to rare groups.

METHODS: The FA genes were analyzed using a next generation sequencing approach in two unrelated families.

RESULTS: The analysis identified the same, c.484_485del, homozygous mutation of FANCF in both families. A careful examination of three electively aborted fetuses in one family and one affected girl in the other indicated an association of the FANCF loss-of-function mutation with a severe phenotype characterized by multiple malformations.

CONCLUSION: The systematic use of next generation sequencing will allow the recognition of individuals from rare complementation groups, a better definition of their clinical phenotypes, and consequently, an appropriate genetic counseling. Birth Defects Research (Part A) 103:1003-1010, 2015. © 2015 Wiley Periodicals, Inc.

VL - 103 IS - 12 U1 - http://www.ncbi.nlm.nih.gov/pubmed/26033879?dopt=Abstract ER - TY - JOUR T1 - Analysis of 339 pregnancies in 181 women with 13 different forms of inherited thrombocytopenia. JF - Haematologica Y1 - 2014 A1 - Noris, Patrizia A1 - Schlegel, Nicole A1 - Klersy, Catherine A1 - Heller, Paula G A1 - Civaschi, Elisa A1 - Pujol-Moix, Núria A1 - Fabris, Fabrizio A1 - Favier, Rémi A1 - Gresele, Paolo A1 - Latger-Cannard, Véronique A1 - Cuker, Adam A1 - Nurden, Paquita A1 - Greinacher, Andreas A1 - Cattaneo, Marco A1 - De Candia, Erica A1 - Pecci, Alessandro A1 - Hurtaud-Roux, Marie-Françoise A1 - Glembotsky, Ana C A1 - Muñiz-Diaz, Eduardo A1 - Randi, Maria Luigia A1 - Trillot, Nathalie A1 - Bury, Loredana A1 - Lecompte, Thomas A1 - Marconi, Caterina A1 - Savoia, Anna A1 - Balduini, Carlo L A1 - Bayart, Sophie A1 - Bauters, Anne A1 - Benabdallah-Guedira, Schéhérazade A1 - Boehlen, Françoise A1 - Borg, Jeanne-Yvonne A1 - Bottega, Roberta A1 - Bussel, James A1 - De Rocco, Daniela A1 - de Maistre, Emmanuel A1 - Faleschini, Michela A1 - Falcinelli, Emanuela A1 - Ferrari, Silvia A1 - Ferster, Alina A1 - Fierro, Tiziana A1 - Fleury, Dominique A1 - Fontana, Pierre A1 - James, Chloé A1 - Lanza, Francois A1 - Le Cam Duchez, Véronique A1 - Loffredo, Giuseppe A1 - Magini, Pamela A1 - Martin-Coignard, Dominique A1 - Menard, Fanny A1 - Mercier, Sandra A1 - Mezzasoma, Annamaria A1 - Minuz, Pietro A1 - Nichele, Ilaria A1 - Notarangelo, Lucia D A1 - Pippucci, Tommaso A1 - Podda, Gian Marco A1 - Pouymayou, Catherine A1 - Rigouzzo, Agnes A1 - Royer, Bruno A1 - Sie, Pierre A1 - Siguret, Virginie A1 - Trichet, Catherine A1 - Tucci, Alessandra A1 - Saposnik, Béatrice A1 - Veneri, Dino KW - Adult KW - Female KW - Humans KW - Infant, Newborn KW - Pregnancy KW - Pregnancy Complications, Hematologic KW - Retrospective Studies KW - Thrombocytopenia KW - Young Adult AB -

Pregnancy in women with inherited thrombocytopenias is a major matter of concern as both the mothers and the newborns are potentially at risk of bleeding. However, medical management of this condition cannot be based on evidence because of the lack of consistent information in the literature. To advance knowledge on this matter, we performed a multicentric, retrospective study evaluating 339 pregnancies in 181 women with 13 different forms of inherited thrombocytopenia. Neither the degree of thrombocytopenia nor the severity of bleeding tendency worsened during pregnancy and the course of pregnancy did not differ from that of healthy subjects in terms of miscarriages, fetal bleeding and pre-term births. The degree of thrombocytopenia in the babies was similar to that in the mother. Only 7 of 156 affected newborns had delivery-related bleeding, but 2 of them died of cerebral hemorrhage. The frequency of delivery-related maternal bleeding ranged from 6.8% to 14.2% depending on the definition of abnormal blood loss, suggesting that the risk of abnormal blood loss was increased with respect to the general population. However, no mother died or had to undergo hysterectomy to arrest bleeding. The search for parameters predicting delivery-related bleeding in the mother suggested that hemorrhages requiring blood transfusion were more frequent in women with history of severe bleedings before pregnancy and with platelet count at delivery below 50 × 10(9)/L.

VL - 99 IS - 8 U1 - http://www.ncbi.nlm.nih.gov/pubmed/24763399?dopt=Abstract ER - TY - JOUR T1 - Molecular analysis of Fanconi anemia: the experience of the Bone Marrow Failure Study Group of the Italian Association of Pediatric Onco-Hematology. JF - Haematologica Y1 - 2014 A1 - De Rocco, Daniela A1 - Bottega, Roberta A1 - Cappelli, Enrico A1 - Cavani, Simona A1 - Criscuolo, Maria A1 - Nicchia, Elena A1 - Corsolini, Fabio A1 - Greco, Chiara A1 - Borriello, Adriana A1 - Svahn, Johanna A1 - Pillon, Marta A1 - Mecucci, Cristina A1 - Casazza, Gabriella A1 - Verzegnassi, Federico A1 - Cugno, Chiara A1 - Locasciulli, Anna A1 - Farruggia, Piero A1 - Longoni, Daniela A1 - Ramenghi, Ugo A1 - Barberi, Walter A1 - Tucci, Fabio A1 - Perrotta, Silverio A1 - Grammatico, Paola A1 - Hanenberg, Helmut A1 - Della Ragione, Fulvio A1 - Dufour, Carlo A1 - Savoia, Anna KW - Amino Acid Substitution KW - Cell Line KW - Cohort Studies KW - Computational Biology KW - Databases, Nucleic Acid KW - Fanconi Anemia KW - Fanconi Anemia Complementation Group Proteins KW - Founder Effect KW - Genotype KW - Humans KW - Italy KW - Mosaicism KW - Mutation KW - Polymorphism, Single Nucleotide AB -

Fanconi anemia is an inherited disease characterized by congenital malformations, pancytopenia, cancer predisposition, and sensitivity to cross-linking agents. The molecular diagnosis of Fanconi anemia is relatively complex for several aspects including genetic heterogeneity with mutations in at least 16 different genes. In this paper, we report the mutations identified in 100 unrelated probands enrolled into the National Network of the Italian Association of Pediatric Hematoly and Oncology. In approximately half of these cases, mutational screening was carried out after retroviral complementation analyses or protein analysis. In the other half, the analysis was performed on the most frequently mutated genes or using a next generation sequencing approach. We identified 108 distinct variants of the FANCA, FANCG, FANCC, FANCD2, and FANCB genes in 85, 9, 3, 2, and 1 families, respectively. Despite the relatively high number of private mutations, 45 of which are novel Fanconi anemia alleles, 26% of the FANCA alleles are due to 5 distinct mutations. Most of the mutations are large genomic deletions and nonsense or frameshift mutations, although we identified a series of missense mutations, whose pathogenetic role was not always certain. The molecular diagnosis of Fanconi anemia is still a tiered procedure that requires identifying candidate genes to avoid useless sequencing. Introduction of next generation sequencing strategies will greatly improve the diagnostic process, allowing a rapid analysis of all the genes.

VL - 99 IS - 6 U1 - http://www.ncbi.nlm.nih.gov/pubmed/24584348?dopt=Abstract ER - TY - JOUR T1 - MYH9-related disease: five novel mutations expanding the spectrum of causative mutations and confirming genotype/phenotype correlations. JF - Eur J Med Genet Y1 - 2013 A1 - De Rocco, Daniela A1 - Zieger, Barbara A1 - Platokouki, Helen A1 - Heller, Paula G A1 - Pastore, Annalisa A1 - Bottega, Roberta A1 - Noris, Patrizia A1 - Barozzi, Serena A1 - Glembotsky, Ana C A1 - Pergantou, Helen A1 - Balduini, Carlo L A1 - Savoia, Anna A1 - Pecci, Alessandro KW - Adolescent KW - Adult KW - Amino Acid Sequence KW - Amino Acid Substitution KW - Base Sequence KW - Child KW - Child, Preschool KW - Exons KW - Female KW - Genes, Dominant KW - Genetic Association Studies KW - Humans KW - Male KW - Middle Aged KW - Models, Molecular KW - Molecular Motor Proteins KW - Molecular Sequence Data KW - Mutation KW - Myosin Heavy Chains KW - Pedigree KW - Protein Conformation KW - Sequence Alignment KW - Syndrome KW - Thrombocytopenia KW - Young Adult AB -

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.

VL - 56 IS - 1 U1 - http://www.ncbi.nlm.nih.gov/pubmed/23123319?dopt=Abstract ER - TY - JOUR T1 - Clinical and laboratory features of 103 patients from 42 Italian families with inherited thrombocytopenia derived from the monoallelic Ala156Val mutation of GPIbα (Bolzano mutation). JF - Haematologica Y1 - 2012 A1 - Noris, Patrizia A1 - Perrotta, Silverio A1 - Bottega, Roberta A1 - Pecci, Alessandro A1 - Melazzini, Federica A1 - Civaschi, Elisa A1 - Russo, Sabina A1 - Magrin, Silvana A1 - Loffredo, Giuseppe A1 - Di Salvo, Veronica A1 - Russo, Giovanna A1 - Casale, Maddalena A1 - De Rocco, Daniela A1 - Grignani, Claudio A1 - Cattaneo, Marco A1 - Baronci, Carlo A1 - Dragani, Alfredo A1 - Albano, Veronica A1 - Jankovic, Momcilo A1 - Scianguetta, Saverio A1 - Savoia, Anna A1 - Balduini, Carlo L KW - Adolescent KW - Adult KW - Aged KW - Aged, 80 and over KW - Bernard-Soulier Syndrome KW - Child KW - Child, Preschool KW - Family Health KW - Female KW - Heterozygote KW - Humans KW - Infant KW - Italy KW - Male KW - Membrane Glycoproteins KW - Middle Aged KW - Mutation, Missense KW - Platelet Aggregation KW - Platelet Count KW - Platelet Glycoprotein GPIb-IX Complex KW - Polymorphism, Genetic KW - Thrombocytopenia KW - Thrombopoietin KW - Tubulin KW - Young Adult AB -

BACKGROUND: Bernard-Soulier syndrome is a very rare form of inherited thrombocytopenia that derives from mutations in GPIbα, GPIbβ, or GPIX and is typically inherited as a recessive disease. However, some years ago it was shown that the monoallelic c.515C>T transition in the GPIBA gene (Bolzano mutation) was responsible for macrothrombocytopenia in a few Italian patients.

DESIGN AND METHODS: Over the past 10 years, we have searched for the Bolzano mutation in all subjects referred to our institutions because of an autosomal, dominant form of thrombocytopenia of unknown origin.

RESULTS: We identified 42 new Italian families (103 cases) with a thrombocytopenia induced by monoallelic Bolzano mutation. Analyses of the geographic origin of affected pedigrees and haplotypes indicated that this mutation originated in southern Italy. Although the clinical expression was variable, patients with this mutation typically had a mild form of Bernard-Soulier syndrome with mild thrombocytopenia and bleeding tendency. The most indicative laboratory findings were enlarged platelets and reduced GPIb/IX/V platelet expression; in vitro platelet aggregation was normal in nearly all of the cases.

CONCLUSIONS: Our study indicates that monoallelic Bolzano mutation is the most frequent cause of inherited thrombocytopenia in Italy, affecting 20% of patients recruited at our institutions during the last 10 years. Because many people from southern Italy have emigrated during the last century, this mutation may have spread to other countries.

VL - 97 IS - 1 U1 - http://www.ncbi.nlm.nih.gov/pubmed/21933849?dopt=Abstract ER - TY - JOUR T1 - Clinical and genetic aspects of Bernard-Soulier syndrome: searching for genotype/phenotype correlations. JF - Haematologica Y1 - 2011 A1 - Savoia, Anna A1 - Pastore, Annalisa A1 - De Rocco, Daniela A1 - Civaschi, Elisa A1 - Di Stazio, Mariateresa A1 - Bottega, Roberta A1 - Melazzini, Federica A1 - Bozzi, Valeria A1 - Pecci, Alessandro A1 - Magrin, Silvana A1 - Balduini, Carlo L A1 - Noris, Patrizia KW - Adolescent KW - Adult KW - Amino Acid Sequence KW - Bernard-Soulier Syndrome KW - Blood Platelets KW - Cell Shape KW - Child KW - Child, Preschool KW - Female KW - Genetic Association Studies KW - Genetic Markers KW - Hemorrhage KW - Homozygote KW - Humans KW - Italy KW - Male KW - Membrane Glycoproteins KW - Middle Aged KW - Molecular Sequence Data KW - Platelet Aggregation KW - Platelet Count KW - Platelet Glycoprotein GPIb-IX Complex KW - Point Mutation KW - Polymerase Chain Reaction KW - Ristocetin KW - Thrombocytopenia KW - von Willebrand Factor KW - Young Adult AB -

BACKGROUND: Bernard-Soulier syndrome is a severe bleeding disease due to a defect of GPIb/IX/V, a platelet complex that binds the von Willebrand factor. Due to the rarity of the disease, there are reports only on a few cases compromising any attempt to establish correlations between genotype and phenotype. In order to identify any associations, we describe the largest case series ever reported, which was evaluated systematically at the same center.

DESIGN AND METHODS: Thirteen patients with the disease and seven obligate carriers were enrolled. We collected clinical aspects and determined platelet features, including number and size, expression of membrane glycoproteins, and ristocetin induced platelet aggregation. Mutations were identified by direct sequencing of the GP1BA, GP1BB, and GP9 genes and their effect was shown by molecular modeling analyses.

RESULTS: Patients all had a moderate thrombocytopenia with giant platelets and a bleeding tendency whose severity varied among individuals. Consistent with expression levels of GPIbα always lower than 10% of control values, platelet aggregation was absent or severely reduced. Homozygous mutations were identified in the GP1BA, GP1BB and GP9 genes; six were novel alterations expected to destabilize the conformation of the respective protein. Except for obligate carriers of a GP9 mutation with a reduced GPIb/IX/V expression and defective aggregation, all the other carriers had no obvious anomalies.

CONCLUSIONS: Regardless of mutations identified, the patients' bleeding diathesis did not correlate with thrombocytopenia, which was always moderate, and platelet GPIbα expression, which was always severely impaired. Obligate carriers had features similar to controls though their GPIb/IX/V expression showed discrepancies. Aware of the limitations of our cohort, we cannot define any correlations. However, further investigations should be encouraged to better understand the causes of this rare and underestimated disease.

VL - 96 IS - 3 U1 - http://www.ncbi.nlm.nih.gov/pubmed/21173099?dopt=Abstract ER -