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The triple A syndrome (AAAS) is an inherited condition associated with mutations in the AAAS gene, which encodes a protein of 546 amino acids known as ALADIN (alacrima achalasia adrenal insufficiency neurologic disorder) whose function is not well understood. This protein belongs to the WD-repeat family of regulatory proteins and is located in the nuclear pore complexes. Only a few cohorts of AAAS patients have been reported and fully characterized. Thus, the objective of the present study was to report on a mini cohort of Italian AAAS patients and to get insights on their predisposing genetic defects. Genetic analysis of AAAS gene in triple A syndrome patient and molecular and functional characterization of the novel identified allelic variants. Here we describe three newly diagnosed cases of AAAS, in whom genetic analysis allowed us to identify two novel allelic variants in the AAAS gene: the frameshift substitution c.765 dupT (p.Gly256Trp fsX67) in exon 8 and the splice site mutation in intron 11(c.997–2 A > G, IVS11-2A > G). Both variants result in a truncated non-functional protein, as we demonstrate by transcript analysis and expression studies. Our findings establish a pathogenic role for both new variants. Moreover, our data highlight the essential role of the C-terminal domain of the protein for its correct targeting and function and underline the importance of sequencing splice sites surrounding the intron–exon junctions to ensure accurate molecular diagnosis and correct genetic counseling in AAAS patients.

Since 2001 the Istituto Superiore di Sanità established a quality assurance programme for molecular genetic testing that covers four pathologies: Cystic Fibrosis (CF), Beta Thalassemia (BT), Fragile X Syndrome (FX), and Familial Adenomatous Polyposis Coli (APC). Since 2009 this activity is an institutional activity and participation is open to both public and private laboratories. Seven rounds have been performed until now and the eighth is in progress. Laboratories receive 4 DNA samples with mock clinical indications. They analyze the samples using their routine procedures. A panel of assessors review the raw data and the reports; all data are managed through a web utility. In 2010 the number of participants was 43, 17, 15, 5 for CF, BT, FX, APC schemes respectively. Genotyping results were correct in 96%, 98.5%, 100%, and 100% of CF, BT, FX, and APC samples, respectively. Interpretation was correct in 74%, 91%, 88%, and 60% of CF, BT, FX, and APC reports, respectively; however in most of them it was not complete but a referral to genetic counseling was given. Reports were satisfactory in more than 60% of samples in all schemes. This work presents the 2010 results in detail comparing our data with those from other European schemes.

Cystic fibrosis (CF) is a common recessive genetic disease caused by mutations in the gene encoding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. More than 1800 different mutations have been described to date. Here, we report 3 novel mutations in CFTR in 3 Italian CF patients. To detect and identify 36 frequent mutations in Caucasians, we used the INNO-LiPA CFTR19 and INNO-LiPA CFTR17+Tn Update kits (Innogenetics; Ghent, Belgium). Our first analysis did not reveal both of the responsible mutations; thus, direct sequencing of the CFTR gene coding region was performed. The 3 patients were compound heterozygous. In one allele, the F508del (c.1521_1523delCTT, p.PHE508del) mutation in exon 11 was observed in each case. For the second allele, in patient No.1, direct sequencing revealed an 11-base pair deletion (GAGGCGATACT) in exon 14 (c.2236_2246del; pGlu746Alafs*29). In patient No. 2, direct sequencing revealed a nonsense mutation at nucleotide 3892 (c.3892G>T) in exon 24. In patient No. 3, direct sequencing revealed a deletion of cytosine in exon 27 (c.4296delC; p.Asn1432Lysfs*16). These 3 novel mutations indicate the production of a truncated protein, which consequently results in a non-functional polypeptide.

β-Thalassemia is the most common autosomal recessive single-gene disorder in Sardinia, where approximately 10.3% of the population is a carrier. Prenatal diagnosis is carried out at 12 weeks of gestation via villocentesis and is commonly aimed at ascertaining the presence or absence of the HBB variant c.118C>T, which is the most common in Sardinia. In this study, we describe for the first time the application of semiconductor sequencing to the non-invasive prenatal diagnosis of β-thalassemia in 37 couples at risk for this variant. In particular, by using a haplotyping-based approach with a hidden Markov model (HMM) and a dedicated pipeline, the two parental haplotypes most likely inherited by the foetus could be established in 30 out of 37 cffDNA samples. Specifically, the paternally inherited haplotype was correctly determined in all 30 of the samples, while the maternal haplotype was incorrectly predicted in six of the 30 genotyped samples. The lack of informative SNPs hampered the inference of both parental haplotypes in the remaining seven samples. As shown in previous studies, we have confirmed that the haplotyping-based approach represents a valuable resource, as it improves the detection of both parental haplotypes inherited by the foetus. In general, our results are encouraging, as we have proven that NIPD is also feasible in couples who are at risk for a monogenic disorder and share the same variant.

Objective he aim of this study was to investigate whether a variation in the genomic copy number (CNV) of the β-defensin cluster could be associated with the predisposition to Chronic Mucocutaneous Candidiasis (CMC) in Sardinian APECED patients. Subjects and methods The β-defensin copy number variation was determined by MLPA analysis in 18 Sardinian APECED patients with CMC and in 21 Sardinian controls. Statistical analyses were performed with ANOVA-one way test. Results No statistically significant results were observed between the patients and controls groups. Conclusions According to the results we have obtained, it appears that either β-defensin genomic CNV is not a modifier locus for CMC susceptibility in APECED patients, or that any effect is too small for it to be detected using such sample size. An extensive study on APECED patients from different geographical areas might reveal the real implication of the β-defensin CNV in the susceptibility to Candida albicans infections. This article is protected by copyright. All rights reserved.

Autoimmune polyendocrine syndrome type 1 (APS1) is a childhood-onset monogenic disorder caused by mutations in the autoimmune regulator (AIRE) gene, including the distinctive R139X in Sardinia. Its rarity and great variability in manifestations/onset ages make early diagnosis difficult. To date, very few longitudinal studies of APS1 patients have been reported.The aim of this study was to describe the features and clinical course of APS1 and correlate them with AIRE and HLA class II genotypes in a large homogeneous cohort of Sardinian patients followed for up to 25 yr.Twenty-two pediatric APS1 patients were studied prospectively.This Sardinian series (female/male ratio, 1.44; median current age, 30.7 yr; range, 1.8-46 yr) showed early disease onset (age range, 0.3-10 yr; median, 3.5 yr) and severe phenotype (on average, seven manifestations per patient). Besides the classic triad of chronic mucocutaneous candidiasis, hypoparathyroidism, and Addison's disease, autoimmune hepatitis was a serious and surprisingly common/early/presenting feature (27%; two deaths), with a 5:1 female bias (median age, 6 yr; range, 2.5-11 yr). By contrast, type 1 diabetes was rare (one patient), and hypothyroidism was not seen. Additional disease components (several of them potentially life-threatening) appeared in adulthood. The major nonsense mutation, R139X, was found in 93% of the mutant AIRE alleles. High-titer interferon (IFN)-ω and IFN-α autoantibodies were detected in all patients tested, even preclinically at 4 months of age in one sibling. HLA alleles appear to influence the exact phenotype-the most interesting apparent association being between HLA-DRB1*0301-DQB1*0201, liver-kidney microsome autoantibodies (anti-CYP1A2), and autoimmune hepatitis.APS1 in Sardinia is characterized by severe phenotype, marked clinical heterogeneity, and relative genetic homogeneity. The single AIRE mutation, R139X, and the anti-IFN-ω and IFN-α autoantibodies are helpful for earlier diagnosis, especially when APS1 presents unusually. HLA genotypes can modify the phenotype.

Background: In Sardinia the mutational spectrum of CFTR gene is well defined. A mutation detection rate of 94% can be achieved by screening for 15 CFTR mutations with a frequency higher than 0.5%. The efficiency of this molecular test suggests that Sardinians may represent a suitable population for a preconceptional screening. Methods: Five hundred couples of Sardinia descent were screened for 38 mutations using a semi-automated reverse-dot blot and PCR-gel electrophoresis assays. This mutation panel included the 15 most frequent CF alleles in Sardinia. Results: We identified 38 CF carriers, revealing an overall frequency of 1/25 (4%). The most common CF allele was the p.Thr338Ile (T338I) (65%), followed by the p.Phe508del (F508del) (22.5%). We also identified one couple at risk and an asymptomatic female homozygote for the p.Thr338Ile allele. Conclusions: In spite of the low number of the couples tested, the results herein reported demonstrate the efficacy and efficiency of the preconceptional screening program and the high participation rate of the Sardinian population (99%).

The Italian scheme of External Quality Assessment for beta-thalassemia started in 2001 as part of a project twice funded by the Italian Ministry of Health and coordinated by the Istituto Superiore di Sanità. To date, five trials have been performed (2001-2004 and 2006). The aim of the Italian scheme is to help public laboratories in improving and reaching a high standard of quality when performing a molecular test. Many laboratories took part in the 5-year project, and their participation was constant during the whole period. The aims of this paper are to describe the genotyping and reporting results as well as focusing on the techniques and the testing strategies adopted to detect mutations. Almost 99% of the alleles analyzed were correctly detected by laboratories, while 0.33% of the analyses gave a wrong result. Reverse dot blot was the most used technique, and it was always used in the strategies adopted by laboratories to detect mutations. The reports sent by laboratories showed incompleteness and heterogeneity; thus, a new model for written reports has been introduced since 2004. It will be interesting to monitor the effects of the reporting model and the output of this educational action in the future.

To investigate the bronchiolitis-associated encephalopathy in critically ill infants.The records of infants with severe bronchiolitis admitted to our intensive care unit between 1991 and 2003 were reviewed. Subjects with underlying neurological disorders were excluded. Encephalopathy was defined as occurrence of seizures or at least two nonconvulsive neurologic manifestations. A semistructured telephone interview investigated long-term neurodevelopmental outcome.Twenty-one infants (11 newborns) were enrolled. All patients required oxygen supplementation and 14 required mechanical ventilation. Encephalopathy occurred in 10 infants, six of whom developed seizures. Encephalopathic infants frequently (six of nine) showed transient EEG abnormalities, and occasionally (one of nine) cranial ultrasound abnormalities. A positive respiratory syncytial virus test was found in five of nine encephalopathic infants. One encephalopathic patient died, while 20 infants clinically normalised before discharge and showed a good neurodevelopmental outcome.Acute encephalopathy was frequently observed in our patients with severe bronchiolitis. Long-term prognosis of encephalopathic infants was good.

This paper describes the first case of Hb Bart's hydrops fetalis syndrome in the Sardinian population. Despite the high frequency of a-thalassemia, fetal hydrops is extraordinarily rare in the Sardinian population because a-thalassemia is more usually the result of the single a-thalassemia globin gene deletion and is very rarely produced by the deletion of two a-globin genes. The fetus, the product of a consanguineous marriage at risk for beta-thalassemia, was monitored by chorionic villi DNA analysis which detected the heterozygous state for the codon 39 nonsense mutation. Follow-up ultrasound examination showed fetal hydrops, which led us to carry out further investigation. Hemoglobin and a-globin gene analysis on cord blood obtained by cordocentesis revealed the homozygous state for the most common deletion ao-thalassemia in Mediterranean populations. Retrospective evaluation of the father's hematological features showed very low MCH-MCV for a beta-thalassemia carrier which may indicate co-inherited a-thalassemia. These findings indicate that careful evaluation of red cell indices of parents at risk for beta-thalassemia and adequate consideration of the consanguinity may point to co-inherited a-thalassemia and lead to the appropriate analysis.

Jeune asphyxiating thoracic dystrophy (JATD; Jeune syndrome, MIM 208500) is a rare autosomal recessive chondrodysplasia, phenotypically overlapping with short-rib polydactyly syndromes (SRPS). JATD typical hallmarks include skeletal abnormalities such as narrow chest, shortened ribs, limbs shortened bones, extra fingers and toes (polydactyly), as well as extraskeletal manifestations (renal, liver and retinal disease). To date, disease-causing mutations have been found in several genes, highlighting a marked genetic heterogeneity that prevents a molecular diagnosis of the disease in most families. Here, we report the results of whole-exome sequencing (WES) carried out in four JATD cases, belonging to three unrelated families of Sardinian origin. The exome analysis allowed to identify mutations not previously reported in the DYNC2H1 (MIM 603297) and WDR60 (MIM 615462) genes, both codifying for ciliary intraflagellar transport components whose mutations are known to cause Jeune syndrome.

Objectives To report the experiences on preimplantation genetic diagnosis (PGD) in couples at risk for s-thalassaemia in Sardinia. Methods 23 couples at risk for s-thalassaemia were included in the PGD programme with a total of 42 cycles performed. Among these, 11 couples were fertile, while the remaining 12 had associated fertility problems. In vitro Fertilization (IVF), PGD and prenatal genetic molecular confirmation protocols and results are reported. Results All the patients followed the protocol of ovarian stimulation, oocyte retrieval, intracytoplasmic sperm injection (ICSI), embryo biopsy and genetic analysis. A total of 272 oocytes were fertilized in the regular way, and embryo biopsy was performed on 202 embryos. Out of these 202 embryos, 192 (95%) were successful. The genetic diagnosis was performed on 150 embryos (78.1%). Ninety-eight were identified as unaffected and 75 were transferred in 31 cycles. In the infertile patient group, two biochemical pregnancies (11.1% per transfer), in the fertile patient group, four clinical pregnancies, two twin and two singleton pregnancies (30.8% per transfer), were obtained. The genetic molecular results were confirmed in all pregnancies by first-trimester chorionic villus sampling (CVS). Conclusion Our study shows that PGD for s-thalassaemia is an available procedure for couples who wish to avoid termination of pregnancy, except in cases where the IVF cycle efficiency is very poor. Copyright © 2004 John Wiley & Sons, Ltd.

The silent beta-thalassemia mutation, beta(+)-101C-->T, is the only mutation currently described in the distal beta-globin CACCC box. We present a novel mutation, a C-->G transversion, in the same position. Expression analysis in heterozygous subjects demonstrated that the mutation determines a 20% reduction in the output of the beta-globin gene. DNA-protein interaction and transactivation analysis correlated the decrease in the beta-globin synthesis with the reduced binding and transactivation of EKLF to the mutant promoter. These data predict that the beta-101C-->G mutation will display a silent thalassemia phenotype similar to that of the beta-101C-->T mutation.

The G protein-coupled receptor TGR5 is a key player of the bile acid signaling network, and its activation has been proved to increase the glycemic control, to enhance energy expenditure and to exert anti-inflammatory actions. Accordingly, TGR5 ligands have emerged in drug discovery and preclinical appraisals as promising agents for the treatment of liver diseases, metabolic syndrome and related disorders.Recent advances in the field of TGR5 modulators are reviewed, with a particular attention on patent applications and peer-reviewed publications in the past 6 years.Activation of TGR5 showed to protect mice from diabesity and insulin resistance, to improve liver functions, as well as to attenuate the development of atherosclerosis. However, although the efficacy of TGR5 agonists in mice is encouraging, further studies are needed to determine their potential in humans and to evaluate carefully the balance between the therapeutic benefits and adverse effects associated with the target. The development of new TGR5 selective ligands to support studies in animal models will surely facilitate the understanding of the complexity of TGR5 signaling network.

In this paper we review the molecular basis of the marked heterogeneity of the thalassemia syndromes as well as the relative implications for carrier screening and prenatal diagnosis. The classical phenotype of heterozygous beta-thalassemia may be modified by a number of environmental and genetic interacting factors--among which the most relevant are: (1) coinheritance of alpha-thalassemia, which may normalize the red blood cell indices; (2) the presence of a mild beta-thalassemia mutation; (3) cotransmission of delta-thalassemia which may reduce the increase of HbA2 typical of heterozygous beta-thalassemia to normal values and (4) the presence of a silent mutation which can be defined only by imbalanced beta-globin chain synthesis. A number of molecular mechanisms are able to produce the non transfusion dependent attenuated forms of thalassemia syndromes referred to as thalassemia intermedia. The most common are homozygosity for mild beta-thalassemia mutations, coinheritance with homozygous beta-thalassemia of alpha-thalassemia or genetic determinants able to sustain a continuous production of HbF in adult life or the presence of heterozygosity for hyperunstable globin variants.

A thirteen-year-old female spayed with a history of hydronephrosis was presented for a routine abdominal ultrasonographic exam. The imaging exam showed a mass involving the pancreas and a large mass affecting the spleen. Exploratory laparotomy evidenced a mass in the pancreas and another involving one-third of the spleen. The patient had partial pancreatectomy and splenectomy. The histopathology report came back with a diagnosis of pancreatic carcinoma. Adjuvant chemotherapy was declined. The cat is still free of gross tumor recurrence and metastatic disease after twenty-six months. Early diagnosed and aggressively treated feline pancreatic carcinoma might yield a favorable prognosis.

Summary In this paper we have reviewed the social and technical aspects of carrier screening and prenatal diagnosis of the inherited haemoglobinopathies. The characteristics of programmes based on carrier screening and prenatal diagnosis ongoing in a number of at-risk Mediterranean populations have been described. The most relevant and common aspects of these programmes are the continuous educational campaign directed to the population at large, the voluntary basis and non-directive counselling. The target population has been most commonly couples before or after marriage. The vast majority of couples counselled accepted prenatal diagnosis. All programmes have encountered a high degree of success as indicated by the marked reduction in the birth rate of infants with thalassaemia major. No significant adverse effects have been reported. A programme with similar characteristics and for which the preliminary results are encouraging, is operating for sickle cell anaemia in the Cuban population. In a population with high frequency of hydrops fetalis, screening for deletion α-thalassaemia is recommended to prevent the negative effects on a pregnant woman of the presence of an hydropic fetus. Thalassaemia carrier screening is now carried out by automatic red cell indices and HbA 2 determination. Definition of atypical cases may require iron studies, globin chain synthesis determination and/or α, β- and δ-globin gene analysis. Identification of the carrier state is followed by definition of the mutation on enzymatically amplified DNA. Known mutations may be detected by restriction endonuclease analysis, non-denaturing polyacrylamide gel electrophoresis, allele-specific primers or allele-specific probes. The most promising procedures, which are also amenable to complete automation are reverse oligonucleotide hybridization and primer-specific amplification. Unknown mutations are defined by denaturing gradient gel electrophoresis, single-strand conformation polymorphism analysis, and chemical mismatch cleavage analysis followed by direct sequencing. The same methods on enzymatically amplified chorionic villus DNA are used for prenatal diagnosis. The potential pitfall resulting from maternal contamination can be avoided by careful dissection of the maternal decidua from the chorion and by the simultaneous amplification of a suitable polymorphism.

Reproductive failure is common in β-thalassemia major patients because of endocrine damage resulting from iron overload. Here 3 full-term pregnancies following spontaneous ovulation in 2 splenectomized β-thalassemia major women are reported. The main echocardiographic parameters, such as left ventricular end-diastolic and end-systolic diameters, fractional shortening and ejection fraction, were within the normal range before pregnancy, but worsened during gestation, and 1 patient developed pre-congestive heart failure. Deferoxamine therapy was continued throughout 2 pregnancies, while in the other it was stopped after 8 weeks: no abnormalities were noted in the children. Thanks to the currently applied therapies, an increased number of pregnancies may now be expected in β-thalassemia major women: it is important to find out more about the pregnancy-related problems and their management in these patients.

Background. Alport syndrome is a clinically and genetically heterogeneous nephropathy characterized by glomerular basement membrane lesions often associated with hearing loss and ocular anomalies. While the X-linked and the autosomal recessive forms are well known, the autosomal dominant form is not well acknowledged. Methods. We have clinically investigated 38 patients with a diagnosis of autosomal dominant Alport syndrome belonging to eight different families. The analysis of the COL4A4 gene was performed by denaturing high performance liquid chromatography and automated DNA sequencing. Results. In our cohort of patients, only 24.3% (9/37) reached end-stage renal disease, at the mean age of 51.2 Correspondence and offprint requests to: Alessandra Renieri, Medical Genetics, Department of Molecular Biology, University of Siena, VLe Bracci, 53100 Siena, Italy. Tel: +39-0577-233303; Fax: +39-0577- 233325; E-mail: renieri@unisi.it years. Four patients had hearing loss (13.3%) and none ocular changes. Molecular analysis revealed eight novel private COL4A4 gene mutations: three frameshift, three missense and two splice-site mutations. Conclusions. These data indicate autosomal dominant Alport syndrome as a disease with a low risk of ocular and hearing anomalies but with a significant risk to develop renal failure although at an older age than the X-linked form. We were unable to demonstrate a genotype-phenotype correlation. Altogether, these data make difficult the differential diagnosis with the benign familial haematuria due to heterozygous mutations of COL4A4 and COL4A3, especially in young patients, and with the X-linked form of Alport syndrome in families where only females are affected. A correct diagnosis and prognosis is based on a comprehensive clinical investigation in as many family members as possible associated with a broadly formal genetic analysis of the pedigree.

Prenatal diagnosis of β-thalassemia was accomplished for the first time in the 1970s by globin chain synthesis analysis on fetal blood obtained by placental aspiration at 18-22 weeks gestation. Since then, the molecular definition of the β- globin gene pathology, the development of procedures of DNA analysis, and the introduction of chorionic villous sampling have dramatically improved prenatal diagnosis of this disease and of related disorders. Much information is now available about the molecular mechanisms of the diseases and the molecular testing is widespread.As prenatal diagnosis has to provide an accurate, safe and early result, an efficient screening of the population and a rapid molecular characterization of the couple at risk, are necessary prerequisites. In the last decades earlier and less invasive approaches for prenatal diagnosis were developed . A overview of the most promising procedure will be done.Moreover, in order to reduce the choice of interrupting the pregnancy in case of affected fetus, Preimplantation or Preconceptional Genetic Diagnosis (PGD) has been setting up for several diseases including thalassemias.

A preventive genetic programme aimed to control beta-thalassemia in the Sardinian population is based on a combination of increased awareness of the population, carrier screening, genetic counselling and prenatal diagnosis. As a result, the registry of thalassemia major demonstrated a profound decline in the incidence of this disease from 1 per 250 to 1 per 1200 live births, with 90% of cases effectively prevented.

This article reviews the molecular bases of alpha- and beta-thalassemias in Sardinia. In addition, it describes the characteristics and the effects of a genetic program designed to prevent homozygous beta-thalassemia. In the large majority of the cases (95.7%), beta-thalassemia is caused by the nonsense mutation at codon 39, followed by frameshifts at codon 6 (2.1%). Homozygous beta-thalassemia most commonly results in thalassemia major, but in a small proportion this genotype produces milder forms referred to as thalassemia intermedia. The reasons for the attenuated forms were determined only in a small proportion of the cases. The reduced clinical severity was due to either of two factors: (a) There could be the presence of cytosine-thymidine (C----T) substitution of position - 158 G gamma, which is able to increase the G gamma chain output (as in homozygotes for frameshift at codon 6 or compound heterozygote for frameshift at codon 6 and codon 39 nonsense mutation). (b) Reduced clinical severity could be the result of co-inheritance of alpha-thalassemia in the form of two alpha-globin gene deletions of functional loss of the alpha 2-globin gene (homozygote for codon 39 nonsense mutation). The most prominent clinical form of alpha-thalassemia is hemoglobin H disease, which may result from the compound heterozygous state for deletion alpha 0- and alpha(+)-thalassemia (in 83.1% of cases) or deletion and nondeletion alpha-thalassemia (in 16.9%). Deletion Hb disease shows a milder clinical picture as compared to the nondeletion form. The most common nondeletion alpha-thalassemia is the ATG----ACG substitution at the initiation codon of the alpha 2 gene. Double heterozygotes of alpha (-alpha/-alpha) and beta-thalassemia or delta- and beta-thalassemia are relatively common and may cause confusion in carrier identification. The preventive program aimed to control beta-thalassemia is based on voluntary carrier screening., counselling, and prenatal diagnosis. Prenatal diagnosis is carried out by dot blot analysis with allelic specific oligonucleotides on amplified trophoblast DNA. This procedure gave very reliable results; in fact, no misdiagnosis has occurred so far. The preventive program was highly effective, resulting in a decline of the incidence of thalassemia major from 1:250 to 1:1,000 live births.

This paper describes the manifestation in a child of a new syndrome characterized by unusual, severe, persistent hyponatremia associated with hyposmolarity, euvolemia, inappropriately concentrated urine and elevated natriuresis. This is the fourth case of this syndrome reported to date, and the first to be reported in a neonate. The clinical features resemble those typically observed in patients with inappropriate antidiuretic hormone secretion, although high arginine vasopressin (AVP) levels are lacking. The findings led the authors to hypothesise a nephrogenic syndrome of inappropriate antidiuresis (NSIAD). The previously described R137C gain-of-function mutation was detected by means of mutation analysis of the V2R gene. Our results indicate that NSIAD is already present during the neonatal period and that molecular analysis of the V2R receptor should therefore be carried out, in all newborns with prolonged euvolemic hyponatremia with hypo-osmolarity, high urinary sodium and normal/low or undetectable AVP levels.

This paper reviews the characteristics and the results of 15 years of experience with a preventive program, based on carrier screening and prenatal diagnosis, designed to control thalassemia major in the Sardinian population. The education of the population about thalassemia and the modalities for its prevention was accomplished via the mass media. Carrier screening was carried out voluntarily on couples of child-bearing age. Prenatal diagnosis was initially carried out by fetal blood analysis; since 1983, it has been done by DNA analysis on non-amplified or amplified DNA. Different chorionic villous sampling procedures have been used. Nowadays, we have adopted the transabdominal approach because, in our experience, it seems to be associated with a low risk (2%) of fetal mortality. At the present time, the beta-thalassemia mutations are detected directly by dot-blot analysis of amplified DNA with 32P- or horseradish peroxidase-labeled allele-specific oligonucleotide probes. Two oligonucleotide probes, one complementary to the codon-39 nonsense mutation, which accounts for 95.7% of the beta-thalassemia chromosomes in the Sardinian population, and the other complementary to the frameshift at codon 6, which is the second most common mutation in our population (2.1%), allow us to make prenatal diagnosis in the large majority of cases. Notwithstanding a careful dissection of maternal decidua from chorionic villi, co-amplification of maternal sequence was detected in 4 out of 425 cases tested by this procedure. In order to avoid this pitfall, the simultaneous amplification of highly polymorphic VNTR (variable number of tandem repeats) segments could be used. On the whole we have so far carried out 2711 prenatal tests: 1130 by fetal blood analysis, 1156 by oligonucleotide hybridization on electrophoretically separated DNA fragments, and 425 by dot-blot analysis on amplified DNA with allele-specific oligonucleotide probes. Two errors occurred by fetal blood analysis and none by DNA analysis. The incidence of thalassemia major declined from 1:250 live births in the absence of prevention to 1:1000 after the establishment of this program, indicating that carrier screening and prenatal diagnosis are effective means for preventing thalassemia major at the population level.

Spinal muscular atrophy (SMA) is an autosomal recessive disease characterized by degeneration of the anterior horn cells of the spinal cord, causing symmetric proximal muscle weakness. SMA is classified in three clinical types, SMA I, SMA II, and SMA III, based on the severity of the symptoms and the age of onset. About 95% of SMA cases are caused by homozygous deletion of the survival motor neuron 1 (SMN1) gene (5q13), or its conversion to SMN2. The molecular diagnosis of this disease is usually carried out by a polymerase chain reaction-restriction fragment length polymorphism approach able to evidence the absence of both SMN1 copies. However, this approach is not able to identify heterozygous healthy carriers, which show a very high frequency in general population (1:50). We used the multiple ligation-dependent probe amplification (MLPA) approach for the molecular diagnosis of SMA in 19 affected patient and in 57 individuals at risk to become healthy carriers. This analysis detected the absence of the homozygous SMN1 in all the investigated cases, and allowed to discriminate between SMN1 deletion and conversion to SMN2 on the basis of the size showed by the peaks specific for the different genes mapped within the SMA critical region. Moreover, MLPA analysis evidenced a condition of the absence of the heterozygous SMN1 in 33 out of the 57 relatives of the affected patients, demonstrating the usefulness of this approach in the identification of healthy carriers. Thus, the MLPA technique represents an easy, low cost, and high throughput system in the molecular diagnosis of SMA, both in affected patients and in healthy carriers.

Summary Background Pemphigus foliaceus (PF) is an autoimmune blistering disease of unknown aetiology, which is endemic in Brazil. Although the pathogenesis of PF is still unknown, proteins of the contact system have been implicated. Objectives As the components of the kinin system may interact with those of the contact system, in this study we evaluated the plasma levels of high-molecular-weight kininogen (HK) and low-molecular-weight kininogen (LK), and the activity of plasma kallikrein, tissue kallikrein and kininase II in plasma of patients with PF presenting with Nikolsky's sign. As kidneys and salivary glands are relevant sources of tissue kallikrein for plasma, we also evaluated urinary/salivary kallikrein and urinary kininase II activities. Methods Fifteen patients and 15 age- and sex-matched controls were studied. Kininogen levels were determined by enzyme-linked immunosorbent assay, and the activities of kallikreins and kininase II were determined using selective chromogenic substrates. Results Compared with controls, plasma HK levels were decreased (P = 0·031), whereas the activities of plasma kallikrein, tissue kallikrein and kininase II in plasma, and the activity of salivary kallikrein, were increased in patients (P

We carried out molecular screening for mutations in the cystic fibrosis transmembrane regulator (CFTR) gene in eight children of Sardinian descent seen because of hypotonic dehydration associated with hyponatremia, hypochloremia, hypokalemia, and metabolic alkalosis; none had pulmonary or pancreatic involvement. All the patients had the T3381 mutation either in homozygosity or compound heterozygosity with another CF mutation. The T3381 mutation was not detected in patients with CF who had classic symptoms or in healthy persons of the same descent. These data suggest that the T3381 mutation is associated with a specific mild CF phenotype.

This study describes the clinical phenotype of the C-->T mutation at position -92 of the beta-globin gene. Excluding two cases with HbA2 levels within the range of the beta-thalassemia carrier state, heterozygotes for this mutation showed normal or borderline red blood cells count, Hb levels, MCV, MCH and HbA2 values, and unbalanced globin chain synthesis. Compound heterozygotes for the -92 C-->T mutation and a beta zero-thalassaemia mutation (beta zero 39) (two cases) or severe beta+-thalassaemia (beta+ IVSII nt 745) (two cases) developed thalassaemia intermedia. According to these characteristics, the -92 promoter mutation should be added to the list of silent beta-thalassaemias.

Summary Stem-cell transplantation can cure β thalassaemia. We aimed to assess whether fetal HLA typing done early in the pregnancy of couples who were at risk of β thalassaemia could provide an alternative to pregnancy termination if the prospect of a bone-marrow transplantation from a family member was available. In our clinic in Sardinia, we did fetal HLA typing for 49 couples at risk of having a baby with β thalassaemia. Two affected children were born and successfully received a transplantation from a family donor. Five non-affected fetuses were HLA compatible with an affected sibling and their cord blood was harvested for a future transplantation.

In this study, we have defined by molecular analysis, the alpha, beta, and delta globin genotype in a group of individuals with normal or thal-like red cell indices but borderline hemoglobin (Hb)A2 levels, who were identified in a program for beta-thal carrier screening. In 37 of 125 individuals with borderline HbA2 levels, we detected a molecular defect in the beta, in both the delta and the beta, or in the alpha globin gene. Specifically seven of these subjects were carriers of the -101 C T mutation, ten of the IVSI nt6 T C mutation, 16 were double heterozygotes for delta and beta thal, and two had the triple alpha globin gene and two the single alpha globin gene deletion. From these results, we may conclude that subjects with borderline HbA2, particularly when they marry a typical beta-thal carrier, should be extensively investigated in order not to miss heterozygous beta-thalassemia.

Autoimmune polyendocrinopathy-candidiasisectodermal dystrophy (APECED; also called APS-1,) is a rare autosomal recessive disorder that is more frequent in certain isolated populations. It is characterized by two of the three major clinical symptoms that may be present: Addison's disease, and/or hypoparathyroidism and/or chronic mucocutaneous candidiasis. We have recently identified the gene for APECED, which we termed AIRE (for autoimmune regulator). AIRE is expressed in thymus, lymph nodes and fetal liver, and encodes a protein with two putative zinc fingers and other motifs suggestive of a transcriptional regulator. Seven mutations have been described to date, including R257X, the predominant Finnish and northern Italian APECED allele, which has also been observed in other patients of diverse origin on different haplotypes. A 13-bp deletion (1094-1106del) has also been observed in several patients of different geo-ethnic origin. The other described mutations appear to be rare. We present mutational analyses of the AIRE gene in ten Sardinian APECED families and show that there is a mutation, R139X, associated with one predominant haplotype unique to the Sardinian patients (18/20 independent alleles). The carrier frequency of R139X in Sardinia is 1.7%, giving an estimated population frequency of APECED of 1/14,400. Using linkage disequilibrium data, the estimated age of the R139X mutation is between 20 and 25 generations. A previously described 13-bp deletion was also observed on an allele of one patient. The identification of a single common Sardinian APECED mutation will facilitate its genetic diagnosis. Given the carrier frequency of R139X in the Sardinian population, AIRE may be implicated in the pathogenesis of other autoimmune diseases in the Sardinian population, particularly those affecting the endocrine system.

The presence of dermatoses is very common in Acquired Human Immunodeficiency Syndrome (AIDS). The present study was undertaken to correlate the various dermatoses with the evolutionary phases of AIDS.We examined 223 HIV-infected patients older than 13 seen at the University of São Paulo, Faculty of Medicine of Ribeirão Preto, from 1989 to 1993. Patients were divided according to the CDC classification and assigned to groups I, II and III (initial stages of AIDS) and to group IV (fully symptomatic stage of AIDS).The mean frequency of dermatoses detected in patients with AIDS was higher compared to the early phases of HIV infection. The most frequently detected dermatoses were, in decreasing order of occurrence, dermatoses of fungal etiology, and desquamating disorders, such as psoriasis, seborrheic dermatitis, xerosis, and viral dermatoses.A careful examination of skin and mucosae may be highly useful for the diagnosis of HIV infection. The number of dermatoses tended to increase during the more advanced stages of infection.The frequency of dermatologic disorders--a common symptom in HIV-infected men and women--was investigated in 223 HIV-positive patients at various stages of disease recruited from the University of Sao Paulo, Faculty of Medicine, in Ribeirao Preto, Brazil, in 1989-93. Of these 223 patients, 152 had full-blown AIDS and the remaining 71 were asymptomatic. A total of 488 dermatoses were diagnosed. The mean number of diagnoses was 2.45 in AIDS patients and 1.61 in the asymptomatic groups. Seborrheic dermatitis, more extensive and of more abrupt onset than that observed in the general population, was the most frequent disorder, affecting 24% of patients in the initial stages of HIV and 30.3% of those with AIDS. The prevalence of viral dermatoses--primarily herpes simplex--was equivalent in both AIDS and asymptomatic patients (14.5% and 14.8%, respectively). Disorders of bacterial etiology--primarily impetigo, ecthyma, and sexually transmitted diseases--were more common in asymptomatic (16.5%) than AIDS patients (3.8%), while fungal dermatoses--predominantly oral moniliasis and tineas--were more frequent in AIDS patients (32.4%) than asymptomatic patients (22.6%). These findings suggest that careful examination of skin and mucosa may be useful for the diagnosis of HIV infection.

[Letter to the Editor] Here we report on a patient who developed hyperbilirubinemia during nilotinib treatment, showing a pattern of UGT1A1 polymorphisms so far undescribed in this clinical setting.

OBJECTIVE: The purpose of the study was to evaluate the feasibility and safety of transabdominal chorionic villus sampling before 9 weeks' gestation. STUDY DESIGN: Two hundred pregnancies at risk for β-thalassemia ( n = 198) or Duchenne muscular dystrophy ( n = 2) underwent transabdominal CVS at 6 through 8 weeks. Sampling success and fetal loss are expressed in percentages. RESULTS: Sampling was successful in all cases (100%). Forty-eight fetuses were affected by β-thalassemia and one by Duchenne muscular dystrophy. The percentage of fetal loss, expressed as a proportion of continuing pregnancies, was 4.0%. All women ( n = 144) have been delivered, and no misdiagnoses have occurred. We observed one anencephalus and one mild limb defect consisting of absence of distal phalanges of index and little fingers of both hands and distal phalanges of both little toes. CONCLUSION: Transabdominal CVS before 9 weeks is a reliable and relatively safe method for prenatal diagnosis in patients at high risk for genetic diseases. However, further studies are necessary to assess the risk to the fetus.

Editor—Crigler-Najjar syndromes (CN, MIM 218800) are inborn errors of metabolism characterised by unconjugated hyperbilirubinaemia resulting from the defective activity of the hepatic enzyme bilirubin uridine 5′-diphosphate-glucuronosyltransferase (B-UGT). CN syndrome has been classified into two types according to the degree of hyperbilirubinaemia and to the response to phenobarbital administration. The more severe CN type I is characterised by severe chronic non-haemolytic unconjugated hyperbilirubinaemia with high levels of serum bilirubin owing to the absence of bilirubin UGT activity. In the milder CN type II, bilirubin UGT activity is only decreased and a consistently significant reduction is obtained with phenobarbital treatment, which does not occur in CN I. Like other members of the UGT isozyme family, the two human liver bilirubin UGT isozymes, UGT1A1 and UGT1D, are encoded by the UGT1 gene complex through a mechanism of alternative splicing. Each gene has a unique promoter and a unique exon 1, while exons 2-5 are common to both genes.1 Most of the enzymatic activity results from the expression of the UGT1A1 gene.2 At the molecular level, CN I results from a number of different defects; nonsense (or frameshift) and missense mutations are represented in almost the same amounts both in homozygosity and in the compound heterozygous state.3 4 The milder phenotype in CN II patients seems to be mainly the result of homozygosity for missense mutations5 and more …

We investigated the molecular bases for a mild phenotype by alpha-, beta- and gamma-globin gene analyses in 22 patients with transfusion-independent thalassemia intermedia (15) or a late-presenting form of thalassemia major (7) originating from Puglia, a region of southern Italy. Twenty-two patients with thalassemia major served as controls. The beta+ IVS-I nt 6 of the beta-globin gene and the C----T substitution at position -158 5' of the G gamma-globin gene were detected more frequently in patients with thalassemia intermedia or late-presenting thalassemia major considered together as compared to those affected by typical transfusion-dependent thalassemia major. Three of 15 patients with thalassemia intermedia had the triple alpha-globin gene arrangement in the heterozygous (2) or homozygous state (1) in association with heterozygous beta zero-thalassemia. From these results, we may conclude that the inheritance of a mild beta-thalassemia allele such as the beta+ IVS-I nt 6 mutation, in the homozygous or heterozygous state, the coinheritance with homozygous beta zero-thalassemia of the -158 (C----T) G gamma gene promoter mutation and the presence of heterozygous beta-thalassemia/triple alpha-globin gene arrangement are the most common reasons accounting for the development of attenuated forms of beta-thalassemia in Puglia.

Cystic fibrosis (CF) is a relatively uncommon genetic disorder in the Sardinian population. In this study, we have defined the frequency of the most common CF mutation (delta F508) and carried out a genotype-phenotype correlation analysis in a group of 21 patients with CF and of Sardinian descent. We detected the delta F508 mutation in 24 (57%) out of the 42 CF chromosome investigated. This mutation was found in the homozygous state in 9 patients and in the heterozygous state in 6 patients. The remaining 6 patients had other mutations. The delta F508 mutation was associated only with the KM19/XV2c 2 1 haplotype. Genotype-phenotype correlation analysis did not give clear-cut results, probably because of the small number of patients investigated. However, out of the four patients with meconium ileus, three were homozygous and one was heterozygous for the delta F508 mutation, confirming that the presence of delta F508 or other severe mutations in the homozygous state is the prerequisite for the development of meconium ileus.

Thalassemias are common autosomal recessive disorders especially in populations of Mediterranean, Middle Eastern, and Far Eastern descent. Relatively high incidence is also observed in people of Asian Indian origin but the incidence is more limited in those of African descent. β Thalassemias are heterogeneous at the molecular level, with more than 150 different molecular defects identified to date. Despite this heterogeneity, each at-risk population has its own spectrum of common mutations, usually from 5 to 10, a finding that simplifies mutation analysis. Homozygosity for β thalassemias usually results in transfusion-dependent thalassemia major and, rarely, in mild non-transfusion-dependent conditions. Molecular diagnosis may be used to define genotypes associated with mild forms. Advances in carrier diagnosis using hematologic analysis followed by mutation analysis have made possible the population screening of women at childbearing age and prenatal diagnosis. This approach in combination with nondirective genetic counseling has resulted in a consistent decline of the birth of affected homozygotes in several Mediterranean at-risk populations, as well as knowledge of the risks of being a carrier. Molecular diagnosis of homozygotes and identification of carriers of β thalassemia may lead to improved clinical management of patients with the disorder and prevention of the birth of affected homozygotes.

The results of 200 antenatal diagnoses in pregnancies at risk for homozygous beta-thalassaemia, carried out on fetal blood samples obtained by placental aspiration in the second trimester, are described. Globin chain synthesis in the fetuses was measured by means of 3H-leucine incorporation and separation of the chains on carboxy-methyl-cellulose columns. Fetal red cell enrichment was performed by NH4Cl-NH4HCO3 differential lysis of maternal cells or anti-i differential agglutination. Sufficient fetal blood for analysis was obtained in 97.5% of the cases. The overall fetal loss rate was 6.5%, but it declined from 10% in the first consecutive 100 cases to 3% in the last 100 cases. Fetal loss was the result of early or late intrauterine death or spontaneous abortion. Forty-two homozygous fetuses had no beta-chain synthesis and one had a very low beta/gamma ratio (0.005). Of the pregnancies, 37 were terminated at parental request and four aborted spontaneously. Absence of beta-chain radioactivity was confirmed in 12 abortuses with suitable cord blood samples for analysis. Two pregnancies with homozygous fetuses were not terminated, as one member of each couple was a devout Catholic. As expected, both infants developed Cooley's anaemia. Follow-up of the 146 infants, diagnosed in utero as non-homozygotes, showed cerebral palsy in one and a small cutaneous needle injury in three. None of these developed homozygous beta-thalassaemia. Even beta-thalassaemia trait with a beta/gamma ratio of 0.046 +/- 0.012 can be distinguished from normal, showing a beta/gamma ratio of 0.086 +/- 0.019 with a high degree of certainty.

We investigated the molecular basis for a mild phenotype in a group of patients with beta + thalassemia originating from Northern Sardinia by definition of the beta-thalassemia mutation, alpha-globin mapping and beta-globin haplotype determination. In nine patients, we detected the compound heterozygous state for the -87 promoter mutation and the codon 39 nonsense mutation; in one patient, we detected the combination of the codon 39 nonsense mutation and beta + IVS-1 nt 6 mutation. These patients were either nontransfusion dependent for survival or became transfusion dependent later. We did not detect the -87 promoter mutation in any of 115 thalassemia major patients originating from the same part of Sardinia, investigated as controls. Heterozygotes for the - 87 promoter mutation showed statistically higher hemoglobin (Hb) levels and larger and better hemoglobinized RBCs as compared with heterozygotes for the codon 39 nonsense mutation. From these data, we conclude that the -87 promoter mutation is a mild thalassemia allele, able to produce a phenotype of intermediate severity even in combination with a beta degree-thalassemia mutant. The coinheritance of alpha-thalassemia or the -++-- 5′ subhaplotype in several cases may have contributed to development of the mild clinical picture. Characterization of the beta-thalassemia mutation in combination with alpha-globin mapping and haplotype analysis may allow a better estimate of the probability of a given clinical phenotype, thus permitting more accurate counseling.