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M Pirastu

Publications and source records attributed to M Pirastu.

At least 37 records · Page 2Linked to original sources

Early and severe neurological features in a Wilson disease patient compound heterozygous for two frameshift mutations.

UNLABELLED: We describe a patient with Wilson disease who presented at 11 years of age with neurological symptoms and subsequent rapid progression of neurological impairment but absent hepatic manifestations. Molecular analysis showed compound heterozygosity for two frameshift mutations, 2299insC and 214delAT, which most likely result in an absent or inactive protein product. Mutation-phenotypic analysis indicates that this genotype does not explain the severe phenotype, suggesting the presence of modifying factors. CONCLUSION: Wilson disease may present even in childhood or adolescence with neurological abnormalities in the absence of hepatic manifestations.

Child↗

Numerical abnormalities of chromosomes 1 and 10 in endometrial adenocarcinoma: fluorescence in situ hybridization analysis of 23 archival paraffin-embedded samples.

Retrospective analysis of chromosomal changes in endometrial carcinoma was performed by fluorescence in situ hybridization on free nuclei isolated from formalin-fixed paraffin-embedded tissue. We examined 23 archival samples for numerical aberrations of chromosomes 1 and 10 with the use of specific DNA probes for the pericentromeric and centromeric regions of these two chromosomes. Numerical aberrations of chromosomes 1 and 10 were detected in 39% of the case analyzed, and the frequency of trisomy 10 tended to increase as the histological grade worsened. Our findings confirm the association of cytogenetic anomalies involving chromosomes 1 and 10 with endometrial carcinoma, as reported by other studies, and suggest that changes in centromere 10 copy number may correlate with the degree of tumor differentiation.

Adult↗

Molecular basis of open-angle glaucoma in Italy.

Glaucoma is a group of ocular diseases characterized by an optic neuropathy in which degeneration of retinal ganglion cells leads to a characteristic excavation of the optic nerve head. Primary open-angle glaucoma (POAG) can be subdivided into two groups according to age of onset:- 1. the more common middle- to late-age onset, chronic open-angle glaucoma (COAG) diagnosed after the age of 40 years; 2. the rarer juvenile open-angle glaucoma (JOAG), which is diagnosed between the age of 3 years and early adulthood. Recently, the gene coding for the trabecular meshwork-induced glucocorticoid response protein (TIGR), located in chromosome 1 (1q23-25), was found mutated in patients affected by POAG. In this work we describe the clinical and molecular genetic features of several Italian families affected by autosomal dominant POAG, collected in various regions of Italy.

Adult↗

A common beta ig-h3 gene mutation (delta f540) in a large cohort of Sardinian Reis Bücklers corneal dystrophy patients. Mutations in brief no. 180. Online.

Reis-Bücklers' corneal dystrophy (RBCD) is a relatively rare autosomal dominant disease originating in the Bowman's membrane, which causes severe visual impairment. Recently RBCD, together with lattice corneal dystrophy type I (LCDI), granular corneal dystrophy (CDGG1) and Avellino stromal dystrophy (ASD), all mapped on 5q31, were found to be associated to four different mutations in the beta ig-h3 gene which codify for kerato-epithelin. We identified several cases of RBCD in Sardinia. We reconstructed through genealogical search two eight generation-families, originating from the same village (Arbus), indicating a common ancestor for RBCD in Sardinia. Linkage studies on these families confirmed the association of the disease with the 5q31 region. Sequence analysis of beta ig-h3 gene revealed a trinucleotide deletion in exon 12, corresponding to the loss of F540 in the protein sequence (delta F540). Our data describe a new mutation in the beta ig-h3 gene causing RBCD. This dominant negative mutation is located in the fourth internal repeat of kerato-epithelin which is a protein domain highly conserved across species. This suggests the basic role of this domain in maintaining the proper kerato-epithelin structure which when altered can cause the typical precipitates in the RBCD cornea.

Chromosomes, Human, Pair 5↗

Rat tyrosine hydroxylase gene polymorphisms.

The rat tyrosine hydroxylase gene (TH) from a panel of outbred and inbred rat strains has been analysed by Southern blotting, restriction-endonuclease mapping and direct sequencing of PCR-amplified products for detecting DNA polymorphisms. Five polymorphic sites have been characterized. This information may be used in pharmacogenetic studies to determine the influence of the TH gene in animal models of affective disorders and addictive behaviours.

Animals↗

[Does a genetic predisposition for infarction expansion exist? Evaluation of genetic polymorphisms of the renin-angiotensin system].

Aim of this study is to carry out a genetic analysis of polymorphisms of the renin-angiotensin system in a genetically homogeneous population, in patients with and without myocardial infarction (AMI) expansion and to evaluate the influence of non genetic, mechanical factors. The study was conducted on 299 patients with first AMI. Ecocardiography studies were performed on all patients on day 1 and 3 from the onset of AMI and before discharge. Eighty-four patients were excluded because of inadequate quality of echocardiograms and 215 (163 males, 52 females) were admitted. Of these, 157 had no evidence of AMI expansion (EXP-) while 58 had expansion (EXP+). DNA was extracted by standard methods from blood samples. Age and gender had no influence on AMI expansion. Anterior infarction (p < 0.000001) and Q-wave infarction (p < 0.00002) were found more frequently in EXP+. Peak of creatine phosphokinase was higher in EXP+ than in EXP- (p < 0.00001). The percent of patients treated with thrombolysis or with hypertension and/or left ventricular hypertrophy was not significantly different in the two groups. AGT MT235 polymorphism of angiotensinogen gene, I/D polymorphism of ACE gene and AT1 A1166C of AT1 receptor of angiotensin II were not significantly different in two groups. Stratified analysis showed that in patients with anterior AMI (n = 87), with a higher risk of AMI expansion, there is a significant difference (p < 0.02) in ACE genotype between EXP- and EXP+. Odds ratio assuming the dominant effect of I allele (II+ ID < DD) was 3.35 (confidence interval 1.41-7.56) with increased risk of expansion. More extension studies are need to verify if these results can contribute to early identification of patients at higher risk and to optimize therapeutic approach.

Aged↗

Deletion in the peripherin/RDS gene in two unrelated Sardinian families with autosomal dominant butterfly-shaped macular dystrophy.

BACKGROUND: Autosomal dominant butterfly-shaped macular dystrophy is associated with different mutations of the peripherin/RDS gene. We studied the phenotype of two families with a novel large deletion in the peripherin/RDS gene. METHODS: Clinical study, fluorescein angiography, color vision testing, automatic perimetry, electrophysiologic studies, and DNA analysis were performed on all the members of the two families. RESULTS: Fundus examination in patients aged 30 to 60 years showed yellow deposits in the macula with a butterfly-shaped pattern. Central choroidal atrophy was present in the older patients only. Macular visual function tests (color vision and central visual field) were abnormal, and electro-oculograms were slightly subnormal in five individuals tested. Electroretinograms and results of dark adaptometry were normal. Linkage analysis with intragenic polymorphic markers and quantitative polymerase chain reaction showed heterozygosity for a large deletion that removed exons 2 and 3 of the peripherin/RDS gene in all affected members of two families. CONCLUSIONS: This deletion escaped detection by direct analysis of amplified exons and was identified by intragenic polymorphic markers analysis, resulting in loss of heterozygosity from affected parents to affected children, and by quantitative polymerase chain reaction. The delineation of the molecular defect associated with the disease in these two families allows us to verify the presence or absence of the disease in clinically unaffected members.

Adolescent↗

Wilson disease mutations associated with uncommon haplotypes in Mediterranean patients.

This study reports 12 novel mutations of the Wilson disease (WD) gene which have been detected by the molecular analysis of 29 patients of Mediterranean descent carrying uncommon chromosomal haplotypes at the WD locus. These mutations include two nonsense, one splice site and nine missense. The missense mutations lie in regions of the WD gene critical for its function, such as the transmembrane region, the transduction domain and the ATP loop and ATP-binding domain, indicating that they are disease-causing mutations. These new findings improve our knowledge for the role played by functional domains on the ATP7B function.

Albania↗

A novel Mediterranean "delta beta-thalassemia" determinant containing the delta (+) 27 and beta (0) 39 point mutations in cis.

The term delta beta-thalassemia with normal HbF has been recently proposed to define heterogenous delta and beta globin gene molecular defects involving the same chromosome in cis. Here, we describe a Sardinian family in which three members showing microcytosis, border-line HbA2 levels and normal HbF proved to be heterozygotes for delta(+) 27 and beta(0) 39 point mutations in cis by allele specific oligonucleotide hybridization as well as by ECO 0 109 I endonuclease digestion and electrophoresis. As some of these beta-thalassemia carriers shows normal HbA2 levels, knowledge of the molecular basis of this novel delta beta-thalassemia silent phenotype would be useful in thalassemia screening and genetic counselling.

Base Sequence↗

Improvement of prenatal diagnosis of Wilson disease using microsatellite markers.

This paper describes a case of prenatal diagnosis for Wilson disease (WD) carried out in an at-risk couple of Sardinian descent, following non-directive genetic counselling. Diagnosis was obtained by using eight microsatellites located within or flanking the WD locus, six of which were 100 per cent and two 50 per cent informative. The use of several markers may limit the occurrence of misdiagnosis resulting from recombination or instability of repeats.

Child, Preschool↗

Role of predisposing and protective HLA-DQA and HLA-DQB alleles in Sardinian multiple sclerosis.

OBJECTIVE: To study the role of HLA genes in susceptibility and resistance to multiple sclerosis (MS) in Sardinian patients. To verify whether HLA-DQA and HLA-DQB genes differed between unrelated (MSU) and related (MSR) patients, and whether relapsing-remitting and chronic progressive forms of MS are immunogenetically distinct entities. DESIGN: Case-control study of HLA-DQA and HLA-DQB gene frequency. SETTING: All patients investigated were followed up by our MS referral centers. PATIENTS: The study involved 116 MSU patients, 67 of whom had a relapsing-remitting form (MSr), 28 of whom had a chronic progressive from-the-onset form (MSc), and 21 of whom had a benign form (MSb), 32 patients with MSR, 19 parents and 27 healthy siblings of patients with MSR, and 86 controls. Selection of patients was random, while control subjects came from families without known immunologic diseases. All patients had definite MS. MAIN OUTCOME MEASURE: Statistical analysis of gene frequencies was conducted with the chi 2 test with correction (Pc) for the alleles investigated, as was decided before the study began. RESULTS: The DQA1*0301 allele was found to be increased in patients (MSU vs controls, Pc = .008; patients with MSc vs controls, Pc = .001; patients with MSR vs controls, Pc = .02; and parents vs controls, Pc = .04), while the DQA1*0102 allele was found to be diminished in patients with MSr vs controls (Pc = .001). Among the DQB genes, the DQB1*0502 allele was diminished in patients with MSr vs controls (Pc = .04), while the sum of DQB1*0201 and *0302 alleles was significantly increased in patients with MSR vs controls (Pc = .003). CONCLUSION: Both HLA-DQA and HLA-DQB genes influence genetic susceptibility and resistance to MS. The roles of these genes differ in the various forms of MS. Patients with MSU and MSR both share HLA-DQA susceptibility genes.

Adolescent↗

Mapping, cloning and genetic characterization of the region containing the Wilson disease gene.

Wilson disease (WD) is an autosomal recessive disorder of copper transport which map to chromosome 13q14.3. In pursuit of the WD gene, we developed yeast artificial chromosome and cosmid contigs, and microsatellite markers which span the WD gene region. Linkage disequilibrium and haplotype analysis of 115 WD families confined the disease locus to a single marker interval. A candidate cDNA clone was mapped to this interval which, as shown in the accompanying paper, is very likely the WD gene. Our haplotype and mutation analyses predict that approximately half of all WD mutations will be rare in the American and Russian populations.

Base Sequence↗

Delta-thalassemia due to a mutation in an erythroid-specific binding protein sequence 3' to the delta-globin gene.

We have previously described a family of Northern Sardinian descent in which the propositus was affected by thalassemia major resulting from compound heterozygosity for codon 39 nonsense mutation and the beta +IVS II nt 745 mutation and in which all heterozygotes for the beta +IVS II nt 745 mutation had normal hemoglobin (Hb) A2 levels. To define the reasons for normal HbA2 levels in otherwise typical beta-thalassemia heterozygotes, we cloned and sequenced the delta-thalassemia gene in cis to the beta +IVS II nt 745 mutation. The sequence analysis showed a single nucleotide substitution (G----A) at position 69 nts (delta +69) downstream to the polyA addition site. Dot blot analysis with an oligonucleotide probe complementary to the delta +69 mutation detected this mutation in several heterozygotes for the beta +IVS II nt 745 mutation from the proband's family, but failed to show it either in a group of normal individuals of the same origin or in nonrelated heterozygotes for the beta +IVS II nt 745 mutation of the same or different descent from the proband. The delta +69 (G----A) mutation may be responsible for the low delta-globin output from the beta +IVS II nt 745 chromosome or could be a silent polymorphism not affecting the function of the delta-globin gene. The normal G at position 69 is part of a sequence very similar to the core DNA (A/T)GATA(A/G) motif (GATA box) that is a binding site for the GATA-1 protein. Gel-retardation assay has shown that a DNA fragment containing the GATA motif with the G----A at position +69 has increased binding affinity for erythroid-specific DNA binding protein(s) as compared with the wild-type sequence. These findings may suggest that the delta +69 mutation is responsible for the deficient function of the in cis delta-globin gene.

Base Sequence↗