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Background Inherited defects decreasing function of the Fas death receptor cause autoimmune lymphoproliferative syndrome and its variant Dianzani’s autoimmune lymphoproliferative disease. Analysis of the lymphocyte transcriptome from a patient with this latter condition detected striking over-expression of osteopontin and tissue inhibitor of metalloproteinases-1. Since previous work on osteopontin had detected increased serum levels in these patients, associated with variations of its gene, the aim of this work was to extend the analysis to tissue inhibitor of metalloproteinases-1. Design and Methods Tissue inhibitor of metalloproteinases-1 levels were evaluated in sera and culture supernatants from patients and controls by enzyme-linked immunosorbent assay. Activation- and Fas-induced cell death were induced, in vitro , using anti-CD3 and anti-Fas antibodies, respectively. Results Tissue inhibitor of metalloproteinases-1 levels were higher in sera from 32 patients (11 with autoimmune lymphoproliferative syndrome and 21 with Dianzani’s autoimmune lymphoproliferative disease) than in 50 healthy controls ( P

Mutations in ribosomal proteins RPS19, RPS24 and RPS17 have been reported in Diamond-Blackfan Anemia (DBA), an autosomal dominant disease characterised by pure red cell aplasia. DBA is the prototype of ribosomapathies: a protein synthesis defect in a tissue with a high cellular turnover is considered the cause of the erythroid progenitor failure. We have created the Diamond-Blackfan Anemia mutation database to curate and record DBA gene mutations, together with their functional consequences and clinical phenotypes. This locus-specific resource is open to future submissions and is available online (http://www.dbagenes.unito.it). It is founded on the Leiden Open (source) Variation Database (LOVD) system and includes data from sequence and structure analysis tools, genomic database resources and published reports. It lists all identified variants and background genomic information. Phenotypic data are accessed by selecting a particular mutation. The database includes 219 unique variants of which 86 are disease-causing mutations. The database will be supplemented with other DBA genes as soon as they are reported and their mutations are identified and it should be of assistance to clinicians and investigators involved in DBA research and care.

Growing evidence suggests a possible relationship between migraine and thrombotic risk factors. The aim of this study was to analyze the possible relationship between migraine and acquired and genetic thrombophilia in a young population. We compared 16 migrainous adolescents, 12 children with tension-type headache, and controls in terms of frequencies of prothrombotic polymorphisms (factor V Leiden, C677T mutation of 5,10 methylenetetrahydrofolate reductase, G20210A mutation of prothrombin), platelet aggregability, anticoagulant antibodies, blood lipid pattern, serum folate and vitamin B12 levels, homocysteinemia, coagulation parameters, and family history for migraine and precocious thrombotic events. This study confirms the link between migraine and increased platelet responsiveness. Overall, 62.5% of migrainous patients carried at least three thrombophilic factors. Our preliminary data suggest that, in order to assess prevention strategies, it could be appropriate to perform a complete thrombophilia screening in young patients suffering from migraine and with a family history of thrombosis.

We describe the onset of cataract in early infancy in a family with hereditary hyperferritinaemia-cataract syndrome. The two probands presented with isolated hyperferritinaemia and had developed cataracts at the age of 18 months. Two members of their family with high ferritin levels (1270–1450 µg/l) had suffered from cataract since childhood. The mutation responsible was a 32G→C change in the lateral bulge of the stem structure of the iron responsive element of the L-ferritin subunit gene. Mutations at this level cause particularly high ferritin levels, whereas the age of cataract onset and its severity are controversial subjects. In our family, early ophthalmic examination ruled out the possibility that cataract was due to age-related persistence of high ferritin levels in the lens and suggested that other factors may modulate the phenotype. Conclusion: cataract may appear early in hereditary hyperferritinaemia-cataract syndrome and this syndrome should be suspected and ferritin levels measured in all cases of cataract in children, even when the onset is in early infancy.

Background Diamond-Blackfan anaemia (DBA) is a rare inherited red cell hypoplasia characterised by a defect in the maturation of erythroid progenitors and in some cases associated with malformations. Patients have an increased risk of solid tumors. Mutations have been found in several ribosomal protein (RP) genes, i.e RPS19, RPS24, RPS17, RPL5, RPL11, RPL35A. Studies in haematopoietic progenitors from patients show that haplo-insufficiency of an RP impairs rRNA processing and ribosome biogenesis. DBA lymphocytes show reduced protein synthesis and fibroblasts display abnormal rRNA processing and impaired proliferation. Results To evaluate the involvement of non-haematopoietic tissues in DBA, we have analysed global gene expression in fibroblasts from DBA patients compared to healthy controls. Microarray expression profiling using Affymetrix GeneChip Human Genome U133A 2.0 Arrays revealed that 421 genes are differentially expressed in DBA patient fibroblasts. These genes include a large cluster of ribosomal proteins and factors involved in protein synthesis and amino acid metabolism, as well as genes associated to cell death, cancer and tissue development. Conclusion This analysis reports for the first time an abnormal gene expression profile in a non-haematopoietic cell type in DBA. These data support the hypothesis that DBA may be due to a defect in general or specific protein synthesis.

Diamond-Blackfan anemia (DBA) is an inherited disease characterized by pure erythroid aplasia. Thirty percent (30%) of patients display malformations, especially of the hands, face, heart, and urogenital tract. DBA has an autosomal dominant pattern of inheritance. De novo mutations are common and familial cases display wide clinical heterogeneity. Twenty-five percent (25%) of patients carry a mutation in the ribosomal protein (RP) S19 gene, whereas mutations in RPS24, RPS17, RPL35A, RPL11, and RPL5 are rare. These genes encode for structural proteins of the ribosome. A link between ribosomal functions and erythroid aplasia is apparent in DBA, but its etiology is not clear. Most authors agree that a defect in protein synthesis in a rapidly proliferating tissue, such as the erythroid bone marrow, may explain the defective erythropoiesis. A total of 77 RPS19 mutations have been described. Most are whole gene deletions, translocations, or truncating mutations (nonsense or frameshift), suggesting that haploinsufficiency is the basis of DBA pathology. A total of 22 missense mutations have also been described and several works have provided in vitro functional data for the mutant proteins. This review looks at the data on all these mutations, proposes a functional classification, and describes six new mutations. It is shown that patients with RPS19 mutations display a poorer response to steroids and a worse long-term prognosis compared to other DBA patients.

Diamond-Blackfan anemia (DBA,#MIM105650) is a rare congenital pure red cell aplasia characterized by nor-mochromic macrocytic anemia, reticulocytopenia, and normocellular bone marrow with a selective deficiency of erythroid precursors. Defects in the RPS19 gene on chromosome 19q13.2 are the main

Diamond Blackfan anemia (DBA, MIM#205900) is a rare, pure red blood cell aplasia of childhood due to an intrinsic defect in erythropoietic progenitors. About 40% of cases show malformations. Anemia is corrected by steroid treatment in half of the patients; non-responders need chronic transfusions or stem cell transplantation. Defects in the RPS19 gene, encoding the ribosomal protein (RP) S19, are the main known cause of DBA and account for more than 25% of patients. Mutations in other RPs (RPS24, RPS17, RPL35a) have been reported in a minority of patients (Gazda et al., 2006; Cmejla et al., 2007; Farrar et al., 2008) and show that DBA is a disorder of ribosome synthesis. Recently, Gadza et al. (2007) reported the involvement of two new genes (RPL5, RPL11) encoding for RPs of the large subunit in a considerable percentage of DBA patients without mutations in RPS19 or RPS24 (10% and 6,5%, respectively). Here we present the results of RPL11 mutation screening in Italian DBA patients without RPS19 or RPS24 mutations. Preliminary data of RPL5 analysis are also reported. The human RPL11 gene includes 6 exons and spans 4622 bp on chromosome 1. We identified 12 heterozygous mutations in 80 analyzed probands (15%), 10 of which were deletions of 1–47 nucleotides causing frameshift and a premature termination; another deletion (12nt) resulted in a loss of 4 aminoacids. One acceptor splice site defect (intron 5) was also detected. RPL11 mutations were spread in all exons except for exon 1. The human RPL5 gene spans 9888 bp on chromosome 1, and includes 8 exons. We identified one heterozygous mutation in RPL5 in 14 analyzed patients (7%); it is a single nucleotide deletion in exon 5 causing frameshift and a premature termination. None of these sequence changes were found on the NCBI SNP dalabase (http://www.ncbi.nlm.nih.gov/SNP/). Our mutations are expected to alter the genetic information drastically and to cause haploinsufficency. Depletion of RPs compromises ribosome biogenesis and disturbs rRNA processing at different levels (Robledo et al. 2008). Interestingly, all mutated patients (11/13) showed one or more somatic malformations; specifically, thumb anomalies and growth retardation were present in 7/11 (64%) and 6/11 (54%) patients, respectively. The erythrocyte adenosine deaminase activity was performed in 6/13 mutated patients; all of them showed an increased activity. The majority of RPL11 mutated patients were transfusion-dependent at last follow-up (58%,7/12); the RPL5 mutated patient was in clinical remission after steroid treatment. No one of the mutated patients has so far developed neoplasia. Our data show that RPL11 mutations are more frequent than expected (Gazda et al. 2007). They seem to confer a relevant association with a malformation phenotype as compared to RPS19 mutations.

The autoimmune lymphoproliferative syndrome (ALPS) is an inherited disorder of lymphocyte apoptosis caused by defects in the Fas apoptotic pathway. It is characterized by the association of chronic lymphoid accumulation and autoimmune manifestations. In a subgroup of patients the disease progresses through antibody deficiency and its clinical and laboratory features overlap those of common variable immunodeficiency (CVID). Some CVID cases are associated with mutations in gene TNFRSF13B, encoding TACI. Aim of this study was to determine whether TNFRSF13B mutations are also associated with ALPS. Methods. Genomic DNA from 31 ALPS patients was extracted from PBMCs after informed consent. Exons and intron-exon boundaries of TNFRSF13B gene were amplified by PCR and sequenced on an ABI PRISM 310 Genetic Analyzer. Results. A T>A transition at nt 275, that determined the non-conservative substitution of Isoleucine with Asparagine (I92N), was found in exon 3 from one patient. The mutation involved the second extracellular cysteine rich domain, which is critical for BAFF binding. It was not found in 100 control chromosomes. The patient showed a classical ALPS phenotype with lymphadenopathy, massive splenomegaly that required splenectomy, hepatomegaly and immune cytopenias (neutropenia and immune thrombocytopenic purpura); he had alopecia and high ANA levels. Serum immunoglobulins were normal (IgG titers at the lower level of the range); lymphocytes showed defective Fas-induced apoptosis. Discussion. TACI mutations might contribute to the ALPS phenotype in some cases. Our data confirm the relationships between ALPS and CVID and provides a possible molecular explanation for overlapping phenotypes.