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Our aim was to evaluate the psychological impact of predictive genetic testing in individuals at-risk for inherited dementia who underwent a structured counseling and testing protocol.Participants were healthy at-risk relatives from families with at least one affected patient, in whom a disease-associated genetic variant had been ascertained. A comprehensive psychological assessment (personality, anxiety and depression, quality of life, coping strategies, resilience and health-related beliefs) was administered at baseline, at 6 months and 12 months follow-up.Twenty-four participants from 13 families were included. Sixteen participants underwent blood sampling and genetic analysis; 6 resulted to be carriers of pathogenic variants (1 in PSEN1, 1 in PSEN2, 4 in GRN). Carriers showed higher score on the Resilience Scale for Adults (RSA) - social competence, and on Multidimensional Health Locus of Control - internal, than noncarriers (P=0.03 for both). Ten at-risk relatives who completed the follow-up showed improvement in RSA - planned future (P=0.01) with respect to baseline.Our case series showed that at-risk individuals undergoing predictive testing showed benefit on personal life and no detrimental impact on a broad range of psychological outcomes. Higher social skills and lower internal health locus of control in carriers may be an early psychological correlate of preclinical dementia.

Background A consensus protocol for genetic counselling and testing of familial dementia, the Italian Dominantly Inherited Alzheimer’s and Frontotemporal Network (IT-DIAfN) protocol, has been developed in Italy by a network of expert dementia centres. The aim of this study is to evaluate feasibility and acceptability of the genetic counselling and testing process, as undertaken according to the IT-DIAfN protocol in one of the IT-DIAfN dementia research centres. Methods The protocol was tested by a multidisciplinary team at the IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy, on affected individuals with suspected inherited forms of Alzheimer’s disease (AD) or frontotemporal dementia (FTD), and to healthy at-risk relatives. The genetic counselling and testing process consisted of (i) pre-test consultation and psychological assessment (ii) genetic testing, (iii) genetic test result disclosure and (iv) follow-up consultation and psychological assessment. Results Twenty affected individuals from 17 families fulfilled the family history criteria of the IT-DIAfN protocol for suspected inherited dementia (17 for AD, 2 for FTD, 1 for inclusion body myopathy with Paget disease of bone and frontotemporal dementia) and were included in the protocol. Nineteen out of 20 affected individuals received the genetic test result (one left after the pre-test consultation being not ready to cope with an unfavourable outcome). A pathogenic mutation was found in 6 affected individuals (1 in PSEN1, 2 in PSEN2, 1 in GRN, 1 in MAPT, 1 in VCP). Eleven healthy at-risk relatives asked to undergo predictive testing and were included in the protocol. Three completed the protocol, including follow-up; one did not ask for the genetic test result after genetic testing; and eight withdrew before the genetic testing, mainly due to an increased awareness about the possible consequences of an unfavourable test result. To date, no catastrophic reactions were reported at the follow-up. Conclusions Our case series shows that a structured genetic counselling and testing protocol for inherited dementia can be implemented in both affected individuals and at-risk relatives in a research setting. The procedure was shown to be safe in terms of occurrence of catastrophic events. A formal validation in larger cohorts is needed.

Pseudohypoparathyroidism type 1A (PHP1A) is usually diagnosed in childhood or early adulthood. We describe the case of a 64-year-old woman admitted to the Neurological Unit for recurrent episodes of loss of consciousness and seizures. Glycemia and ECG were normal, while hypocalcemia was noted. Clinical history revealed carpo-pedal spasm since the age of 30 years, cognitive impairment, hypothyroidism since early adulthood, and menopause at 30 years. She was taking oral calcium and cholecalciferol for chronic hypocalcemia. Physical features suggested Albright’s osteodystrophy. Blood calcium was confirmed low, with increased parathyroid hormone, moderate 25OH-vitamin D deficiency, and normal creatinine. Brain CT scan revealed calcifications of the basal ganglia, cortical and subcortical white matter, and cerebellum. Therapy was switched to oral calcitriol, with normalization of calcium levels; levetiracetam was started and no further seizures occurred. The clinical diagnosis of PHP1A was confirmed by molecular analysis, which demonstrated the heterozygous c.568_571del mutation of the GNAS gene. Our report illustrates the natural history of a patient with PHP1A, which went undiagnosed until the age of 64 years, with multi-hormonal resistance and clinical sequelae evolving throughout life, and underlines the importance of diagnosing this rare disease, which has a great impact on patients and their family life.

Ocular pterygium-digital keloid dysplasia (OPDKD) presents in childhood with ingrowth of vascularized connective tissue on the cornea leading to severely reduced vision. Later the patients develop keloids on digits but are otherwise healthy. The overgrowth in OPDKD affects body parts that typically have lower temperature than 37°C. We present evidence that OPDKD is associated with a temperature sensitive, activating substitution, p.(Asn666Tyr), in PDGFRB. Phosphorylation levels of PDGFRB and downstream targets were higher in OPDKD fibroblasts at 37°C but were further greatly increased at the average corneal temperature of 32°C. This suggests that the substitution cause significant constitutive autoactivation mainly at lower temperature. In contrast, a different substitution in the same codon, p.(Asn666Ser), is associated with Penttinen type of premature aging syndrome. This devastating condition is characterized by widespread tissue degeneration, including pronounced chronic ulcers and osteolytic resorption in distal limbs. In Penttinen syndrome fibroblasts, equal and high levels of phosphorylated PDGFRB was present at both 32°C and 37°C. This indicates that this substitution causes severe constitutive autoactivation of PDGFRB regardless of temperature. In line with this, most downstream targets were not affected by lower temperature. However, STAT1, important for tissue wasting, did show further increased phosphorylation at 32°C. Temperature-dependent autoactivation offers an explanation to the strikingly different clinical outcomes of substitutions in the Asn666 codon of PDGFRB.

Colorectal cancer patients’ responses to neoadjuvant therapy undergo broad inter-individual variations. The aim of this systematic review is to identify a molecular signature that is predictive of colon cancer downstaging and/or downgrading after neoadjuvant therapy. Among the hundreds analysed in the available studies, only 19 messenger-RNAs (mRNAs) and six micro-RNAs (miRNAs) were differentially expressed in responders versus non-responders in two or more independent studies. Therefore, a mRNA/miRNA signature can be designed accordingly, with limitations caused by the retrospective nature of these studies, the heterogeneity in study designs and the downgrading/downstaging assessment criteria. This signature can be proposed to tailor neoadjuvant therapy regimens on an individual basis.

Author(s): Bonvicini, Cristian; Scassellati, Catia; Benussi, Luisa; Di Maria, Emilio; Maj, Carlo; Ciani, Miriam; Fostinelli, Silvia; Mega, Anna; Bocchetta, Martina; Lanzi, Gaetana; Giacopuzzi, Edoardo; Ferraboli, Sergio; Pievani, Michela; Fedi, Virginia; Defanti, Carlo Alberto; Giliani, Silvia; Alzheimer’s Disease Neuroimaging Initiative; Frisoni, Giovanni Battista; Ghidoni, Roberta; Gennarelli, Massimo | Abstract: BackgroundEarly onset dementias (EOD) are rare neurodegenerative dementias that present before 65 years. Genetic factors have a substantially higher pathogenetic contribution in EOD patients than in late onset dementia.ObjectiveTo identify known and/or novel rare variants in major candidate genes associated to EOD by high-throughput sequencing. Common-risk variants of apolipoprotein E (APOE) and prion protein (PRNP) genes were also assessed.MethodsWe studied 22 EOD patients recruited in Memory Clinics, in the context of studies investigating genetic forms of dementia. Two methodological approaches were applied for the target-Next Generation Sequencing (NGS) analysis of these patients. In addition, we performed progranulin plasma dosage, C9Orf72 hexanucleotide repeat expansion analysis, and APOE genotyping.ResultsWe detected three rare known pathogenic mutations in the GRN and PSEN2 genes and eleven unknown-impact mutations in the GRN, VCP, MAPT, FUS, TREM2, and NOTCH3 genes. Six patients were carriers of only common risk variants (APOE and PRNP), and one did not show any risk mutation/variant. Overall, 69% (n = 9) of our early onset Alzheimer's disease (EAOD) patients, compared with 34% (n = 13) of sporadic late onset Alzheimer's disease (LOAD) patients and 27% (n = 73) of non-affected controls (ADNI, whole genome data), were carriers of at least two rare/common risk variants in the analyzed candidate genes panel, excluding the full penetrant mutations.ConclusionThis study suggests that EOD patients without full penetrant mutations are characterized by higher probability to carry polygenic risk alleles that patients with LOAD forms. This finding is in line with recently reported evidence, thus suggesting that the genetic risk factors identified in LOAD might modulate the risk also in EOAD.

We have investigated a distinct disorder with progressive corneal neovascularization, keloid formation, chronic skin ulcers, wasting of subcutaneous tissue, flexion contractures of the fingers, and acro-osteolysis. In six affected individuals from four families, we found one of two recurrent variants in discoidin domain receptor tyrosine kinase 2 (DDR2): c.1829T>C (p.Leu610Pro) or c.2219A>G (p.Tyr740Cys). DDR2 encodes a collagen-responsive receptor tyrosine kinase that regulates connective-tissue formation. In three of the families, affected individuals comprise singleton adult individuals, and parental samples were not available for verification of the de novo occurrence of the DDR2 variants. In the fourth family, a mother and two of her children were affected, and the c.2219A>G missense variant was proven to be de novo in the mother. Phosphorylation of DDR2 was increased in fibroblasts from affected individuals, suggesting reduced receptor autoinhibition and ligand-independent kinase activation. Evidence for activation of other growth-regulatory signaling pathways was not found. Finally, we found that the protein kinase inhibitor dasatinib prevented DDR2 autophosphorylation in fibroblasts, suggesting an approach to treatment. We propose this progressive, fibrotic condition should be designated as Warburg-Cinotti syndrome.

BackgroundThe existing frameworks for the evaluation of genetic and genomic applications clearly address the technical and clinical value of a test, but are less concerned with the way genetic services are delivered and organized. We therefore aimed to develop a comprehensive new framework that includes an assessment of service delivery.MethodsA new framework was built on the evaluation dimensions identified through a systematic review of the existing frameworks and a Delphi survey of Italian experts in public health genomics.ResultsOur framework has four sections. The first two sections, respectively, guide the evidence collection process for the genetic test (analytic validity; clinical validity; clinical utility; personal utility) and its delivery models (organizational aspects; economic evaluation; ethical, legal and social implications; patient perspective). The third section guides the formulation of the research priorities to be addressed in future research. Finally, the fourth section suggests three criteria to summarize the collected evidence (net benefit, cost-effectiveness, feasibility).ConclusionWe have successfully developed an evaluation framework for the evaluation of genetic tests that includes an assessment of service delivery. It also introduces some neglected evaluation dimensions such as personal utility and patient perspective.

Though the basic pathophysiology of psychosis is largely unknown, there is reliable evidence that genes contribute to its aetiology. Epidemiologic studies suggested that chronic use of cannabis is a risk factor for the development of psychosis. Recent researches have focused on the identification of genetic variants that moderate the effect of cannabis on psychosis occurrence. We undertook a systematic review of primary studies that reported the direct measures of genetic risk in the association between cannabis use and psychosis considering cannabis use as an environmental factor under the gene-environment interaction model. The initial search from PubMed revealed 187 records, of which 113 were excluded on reading the abstract. Of 74 papers screened in full, 60 were reviews, 14 were included for data extraction. We report a structured summary of populations studied, study design, evaluations of cannabis use, genetic variations, outcome measures and main results. The 14 primary studies included in the survey applied the candidate gene approach, COMT being the most investigated; also CNR1, BDNF and SLC6A4 were examined; a novel candidate gene, AKT1, was identified through a multistage approach. Few candidate genes were investigated, and reliable replications were provided only for AKT1. Studies were heterogeneous in terms of experimental design and outcome measures, thus hampering an effective synthesis. We conclude that additional primary studies are warranted. An effort in harmonisation of data, coupled with the recent advances in genetic technologies, should be encouraged.

We describe three unrelated patients of European descent carrying an overlapping 3q26.33–3q27.2 microdeletion who share common clinical features: neonatal hypotonia, severe feeding problems, specific facial features, abnormal dentition, recurrent upper airways infections, developmental delay and severe growth impairment. One of the patients carries a smaller deletion and presents a milder phenotype. We propose that 3q26.33–3q27.2 microdeletion may represent a novel condition caused by the haploinsufficiency of dosage sensitive genes, several of which are involved in brain development.

Mild cognitive impairment is often considered a transitional condition prodromal to Alzheimer's disease. The dissection of genetic risk factors predisposing to mild cognitive impairment is paramount to assess the individual predisposition and reliably evaluate the effectiveness of early therapeutic interventions. We designed a cross-sectional analysis to test whether the occurrence of mild cognitive impairment is influenced by variations of the tau protein gene. The genotypes of seven polymorphisms tagging the major tau haplotypes were assayed on 186 patients with amnestic mild cognitive impairment and 191 unrelated controls. Association study was conducted by logistic regression including APOE genotype and age as covariates. Case-control analysis showed that the common H1 haplotype is significantly overrepresented in patients (OR, 95% CI: 2.31, 1.52-3.51; p

tion causing FA is an expanded GAA repeat in the gene encoding the frataxin protein [6] . Ninety-six percent of patients are homozygous for GAA expansion. Frataxin point mutations have been found in the remaining patients who are heterozygous for the expanded allele [7] . The phenotypic features of patients harboring point mutations may include classical symptomatology or may differ from classic FA [7, 8] . We report on 2 siblings with atypical clinical presentation during the first years of the disease, which caused initial clinical confusion and a delay in making a correct diagnosis. Molecular testing demonstrated that both patients are compound heterozygous for GAA expansion and have a novel point mutation (c.165 + 1 G ] A) which involves the consensus GT dinucleotide in the 3 splice acceptor site of intron 1 of the frataxin gene.

Huntington's disease (HD) is a late-onset, autosomal dominant neurodegenerative disease caused by a CAG trinucleotide expansion. The number of repeats on the HD chromosome explains most of the variability in age of onset, but genetic factors other than the HD gene are responsible for part of the residual variance. Based on the role played by the brain derived neurotrophic factor (BDNF) in neurodysfunction and neurodegeneration in HD, we searched for novel polymorphisms in the neuron restrictive silencer element located in the BDNF promoter. Then, the effect of the Val66Met variant in determining age of onset was tested in a large sample of HD carriers by using a multivariate regression approach. The CAG repeat number accounted for 62% of the variance. After correction for the predominant effect of the CAG expansion, no multiple regression model provided evidence of association between the Val66Met genotype and variation in age-at-onset. Additional studies are warranted to further investigate BDNF as genetic modifier of the HD phenotype.

Friedreich ataxia (FRDA), an autosomal recessive neurodegenerative disease, is associated with an unstable expansion of a GAA trinucleotide repeat in the first intron of the frataxin gene on chromosome 9q13. Unequivocal molecular characterization of the FRDA triplet expansion requires the use of different PCR protocols to amplify normal and mutated alleles combined with Southern blotting analysis to accurately size the expansion. Nevertheless, expansion detection by PCR may be somewhat problematic in heterozygous individuals. The purpose of this study was to evaluate triplet repeat primed PCR (TP PCR) as a screening method for FRDA diagnosis in the diagnostic laboratory. Fifty-four cases referred either to confirm the diagnosis of FRDA or to detect carrier status were re-evaluated by the TP PCR method. The TP PCR assay correctly identified the FRDA status in all 54 individuals tested including homozygous expansions (9 individuals), heterozygous expansions (20 individuals), and non-carriers (25 individuals). Results showed 100% concordance with those obtained by Southern blot analysis. TP PCR allowed us to identify the expanded alleles or to demonstrate their absence in DNA samples where conventional PCR procedures failed to give a reliable result. TP PCR represents an additional valuable tool for mutation detection in FRDA patients and carriers, but also can be used as screening test in a diagnostic laboratory.

A spontaneous autosomal recessive mutation was identified in the Sprague-Dawley rat strain with an early onset sensory neuropathy. The main clinical features of the mutation (mutilated foot, mf ), detectable shortly after birth, include ataxia, insensitivity to pain and foot ulceration. The pathological features include a severe reduction in the number of sensory ganglia and fibres. This mutant is therefore an excellent model for human hereditary sensory neuropathies. Here, we demonstrate that the mf locus maps to the distal end of rat chromosome 14, a region syntenic to human 2p13-p16 and proximal mouse 11. Sequence analysis of four candidate genes in this interval revealed a 1349G>A mutation in the chaperonin (delta) subunit 4 (Cct4) gene associated with the mf mutant. This change resulted in the substitution of a highly conserved cysteine for tyrosine at amino acid 450. Although we did not identify a mutation in the human CCT4 gene in a set of HSN patients, this result clearly demonstrates the pathological consequences of a defect in Cct4, a subunit of CCT (cytosolic chaperonin-containing t-complex peptide-1), involved in folding tubulin, actin and other cytosolic proteins. This is the first report of a mutation in a molecular chaperonin causing a hereditary neuropathy and raises the possibility that mis-folding proteins may be a cause of this group of neuropathies.

Diffusion datasets were corrected for motion and eddy current distortions (Smith et al., 2004) and then processed with a Spherical Deconvolution algorithm based on a damped version of the Richardson-Lucy algorithm (Dell’acqua et al., 2010, Dell’Acqua et al., 2013). Tractography was performed following the method described in (Catani et al., 2012). We dissected fiftyfive frontal tracts including U-shaped fibers. For each dissection FA (Basser and Pierpaoli, 1996) and hindrance modulated oriented anisotropy (HMOA) (Dell’Acqua et al., 2013) were extracted as an indirect measure of the tract integrity and correlated with the age of the participants regressing out the level of education. P values are presented after false discovery rate (FDR) correction for multiple comparisons (* p < 0.05 ; ** p < 0.01 ; *** p < 0.001). Results: Aging was significantly associated with a decrease of FA (r1⁄4 0.501*) and OA (r1⁄4 0.508**) in the frontal projections of the corpus callosum. Aging was also associated with a decrease of OA in the right frontal lobe including the SLF I (r 1⁄4 0.401**) and SLF III (r 1⁄4 0.576***) branches of the superior longitudinal fasciculus, inferior fronto-occipital fasciculus (r 1⁄4 0.331*), fronto-thalamic projections (r 1⁄4 0.515***). In the left hemisphere, OA measure also decreased with aging for the frontal inferior longitudinal fasciculus (r1⁄4 0.542***) and the frontal orbito-polar tract (r 1⁄4 0.542***). Results are summarized in Figure 1. Conclusions: We confirmed preliminary evidences reporting reduced integrity in the frontal portion of the corpus callosum associated with aging (Lebel et al., 2010). This commissural decline may explain the increased reaction times associated with aging reported in tasks requiring interhemispheric transfer (Reuter-Lorenz and Stanczak, 2000). Our results also suggest for the first time that aging alters significantly other tracts in the right hemisphere which brings up interesting pathophysiological hypotheses for ageing decline in visuospatial and verbal working memory, memory encoding and retrieval, reward-based associative learning that can be tested in the elderly (Cabeza and Dennis, 2012). IC-P-069 ITALIAN NETWORK FOR AUTOSOMAL DOMINANTALZHEIMER’S DISEASE AND FRONTOTEMPORAL LOBAR DEGENERATION (ITALIANDIAFN) Martina Bocchetta, Michela Pievani, Claudio Babiloni, Amalia C. Bruni, Elio Scarpini, Sandro Sorbi, Fabrizio Tagliavini, Alessandro Padovani, Luisa Benussi, Livia Bernardi, Giuliano Binetti, Barbara Borroni, Giuseppe Di Fede, Emilio Di Maria, Silvia Fostinelli, Daniela Galimberti, Massimo Gennarelli, Roberta Ghidoni, Nicola Marzano, Anna Mega, Benedetta Nacmias, Irene Piaceri, Corinna Porteri, Giacomina Rossi, Silvia Suardi, Fabrizio Vecchio, Giovanni B. Frisoni, IRCCS Centro S. Giovanni di Dio, Fatebenefratelli, Brescia, Italy; IRCCS Fatebenefratelli, Brescia, Italy; 3 University of Rome "La Sapienza", Rome, Italy; 4 Centro Regionale di Neurogenetica, Lamezia Terme (CZ), Italy; 5 Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy; University of Florence, Florence, Italy; IRCCS Foundation "Carlo Besta" Neurological Institute, Milano, Italy; 8 University of Brescia, Brescia, Italy; 9 IRCCS Instituto Centro S. Giovanni di Dio Fatebenefratelli, Brescia, Italy; 10 Centro Regionale di Neurogenetica, Lamezia Terme, Italy; IRCCS Foundation "Carlo Besta" Neurological Institute, Milan, Italy; University of Genova, Genova, Italy; 13 IRCCS Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy; University of Milan, Ospedale Policlinico, Milan, Italy; IRCCS Centro San Giovanni di Dio, Fatebenefratelli, Brescia, Italy; 16 University of Florence, Florence, Italy; 17 IRCCS Fondazione Instituto Neurologico Carlo Besta, Milano, Italy; 18 IRCCS Fondazione Instituto Neurologico Carlo Besta, Milan, Italy; IRCCS Instituto San Giovanni di Dio Fatebenefratelli, Brecia, Italy. Contact e-mail: mbocchetta@ fatebenefratelli.it

EGR2/Krox-20, a Cys2-His2 zinc finger transcription factor, plays an essential role in the regulation of myelination in the peripheral nervous system. Dominant and recessive mutations in EGR2 are associated with peripheral myelinopathies, such as Charcot-Marie-Tooth disease type 1, Dejerine-Sottas syndrome, and congenital hypomyelinating neuropathy. One recessive mutation (I268N) is known to affect the inhibitory domain that binds the NAB transcriptional corepressors, NAB1 and NAB2. This mutation abolishes the interaction of EGR2 with the NAB corepressors and thereby increases transcriptional activity. Therefore, we hypothesized that mutations in the EGR2-interacting domains of NAB1 and NAB2 might be associated with the pathogenesis of inherited peripheral neuropathies in currently unexplained cases. However, screening 87 such cases failed to identify any disease-causing mutations within the EGR2-interacting domains of either NAB1 or NAB2. A further mutation analysis of the complete coding regions of NAB1 and NAB2 in these genomic DNA samples did not uncover any disease-causing mutation. Therefore, our analysis indicates that mutations in the human NABI and NAB2 genes are most likely not involved in the pathogenesis of peripheral neuropathies.

The diagnosis of Huntington's disease (HD) may be uncertain in patients without a positive family history, particularly when atypical clinical features are present. We examined the expanded trinucleotide (CAG) repeat sequence in the IT15 gene of 27 'sporadic' cases, classified as having clinically probable or clinically doubtful HD. An abnormal number of CAG repeats (42-85) were found in 14 patients. Mutation analysis confirmed the diagnosis in 63.6% of patients with clinically probable HD and in 43.7% of patients with clinically doubtful HD. DNA analysis allows an accurate diagnosis of apparently 'sporadic' HD patients and has important implications for genetic counselling.

Polyfibromatosis is a rare fibrosing condition characterized by fibromatosis in different body areas and by keloid formation, and which can be associated with arthropathy and osteolysis. Familial occurrence has been described, but the cause remains unknown. Here, we describe a patient with characteristics of polyfibromatosis with arthropathy who had in addition severe conjunctival fibrosis, distinctive face, gingival overgrowth, and pigmented keloids. We discuss the resemblances and differences with polyfibromatosis and descriptions of other, similar patients. We conclude that at present it remains uncertain whether the patient has a variant of polyfibromatosis or a separate entity.

The 19q13 microdeletion syndrome is a recently identified disorder of which very few cases have been reported so far. Growth deficiency, microcephaly, ectodermal anomalies and intellectual disability are the major features reported in all the described cases. The critical region has been estimated to span 750 Kb. We report an Italian patient carrying a de novo 1.37 Mb deletion in chromosome 19q13, who presented all the cardinal features of the syndrome, and multiple pituitary hormone deficiency. Our findings might contribute to further refine the critical region to 460 Kb and restrict the list of candidate genes.

Background: Huntington’s disease (HD) is a rare triplet repeat (CAG) disorder. Advanced, multi-centre, multi-national research frameworks are needed to study simultaneously multiple complementary aspects of HD. This includes the natural history of HD, its management and the collection of clinical information and biosamples for research. Methods: We report on cross-sectional data of the first 1766 participants in REGISTRY, the European Huntington’s Disease Network’s (EHDN), multi-lingual, multi-national prospective observational study of HD in Europe. Data collection (demographics, phenotype, genotype, medication, co-morbidities, biosamples) followed a standard protocol. Results: Phenotype, and the HD genotype, of manifest HD participants across different European regions was similar. Motor onset was most common (48%) with a non-motor onset in more than a third of participants. Motor signs increased, and cognitive abilities and functional capacity declined as the disease burden (CAGn-35.5) X age) increased. A life-time history of behavioural symptoms was common, but the behavioural score was not related to disease burden. One fifth of participants had severe psychiatric problems, e.g. suicidal ideation and attempts, and/or irritability/aggression, with psychosis being less common. Participants on anti-dyskinetic medication had a higher motor and lower cognitive score, were older, and more prone to physical trauma. A higher motor and a lower cognitive score predicted more advanced disease. Conclusions: The unparalleled collection of clinical data and biomaterials within the EHDN’s REGISTRY can expedite the search for disease modifiers (genetic and environmental) of age at onset and disease progression that could be harnessed for the development of novel treatments.

Current literature provides more than 30 patients with interstitial deletions in chromosome 2q31q33. Only a few of them were studied using high-resolution methods. Among these, two patients had presented with a particular consistence of some clinical features associated to a deletion between bands q31.2 and q32.3 of chromosome 2. This clinical pattern, labeled as "2q31.2q32.3 syndrome," consists of multiple dysmorphisms, developmental delay, mental retardation and behavioural disturbances. We report an adult female patient with a 4.4 Mb deletion in the 2q31.2q32.3 region, showing facial dysmorphisms, mental retardation and absence of speech. The region overlaps with the deletion found in the two cases previously reported. The critical region points to a few genes, namely NEUROD1, ZNF804A, PDE1A, and ITGA4, which are good candidates to explain the cognitive and behavioural phenotype, as well as the severe speech impairment associated with the 2q31.2q32.3 deletion.

Most common inherited form of intellectual disability, fragile X syndrome is associated to an expansion of greater than 200 CGG repeats in the 5′ untranslated region of the FMR1 gene on the X chromosome which causes transcriptional silencing and deficiency of the encoded protein FMRP. Molecular diagnosis is performed through a combination of PCR to identify fewer than 100–150 repeats and of Southern blot analysis to identify longer alleles and the methylation status of the FMR1 promoter. We present a family with one patient with mild mental retardation who showed an atypical profile at Southern analysis due to the -413C > G transversion located in the FMR1 promoter which had been described as possibly associated with mental retardation. We demonstrated this variant in other four family members along three generations, including the maternal grandfather who did not manifest any pathological feature. Though the -413C > G substitution was not found in a large control series, these findings allowed to exclude its role in determining the disease phenotype.

The occurrence of neuropsychiatric symptoms in patients with Alzheimer's disease hampers the clinical management and exacerbates the burden for caregivers. To what extent psychotic symptoms are genetically determined and which are the genes involved has to be established. We tested the hypothesis that the occurrence of delusions and hallucinations in AD is associated with variations in the G72/DAOA gene, which is supposed to play a key role in the glutamate pathway regulated through the NMDA receptors. A panel of single nucleotide polymorphisms were genotyped in a cohort of 185 Alzheimer's disease patients. The analysis demonstrated a nominally significant association (p< 0.05) with one single nucleotide polymorphism (rs2153674). In addition, multivariate regression showed that the rs2153674 genotype accounts for up to 15% of the variance in delusions severity, as assessed by using the Neuropsychiatric Inventory. If the results from the present study will be replicated, the glutamate hypothesis could be invoked to explain the occurrence of psychosis in neurodegenerative disorders.

Use of RNA interference to reduce huntingtin protein (htt) expression in affected brain regions may provide an effective treatment for Huntington disease (HD), but it remains uncertain whether suppression of both wild-type and mutant alleles in a heterozygous patient will provide more benefit than harm. Previous research has shown suppression of just the mutant allele is achievable using siRNA targeted to regions of HD mRNA containing single nucleotide polymorphisms (SNPs). To determine whether more than a minority of patients may be eligible for an allele-specific therapy, we genotyped DNA from 327 unrelated European Caucasian HD patients at 26 SNP sites in the HD gene. Over 86% of the patients were found to be heterozygous for at least one SNP among those tested. Because the sites are genetically linked, one cannot use the heterozygosity rates of the individual SNPs to predict how many sites (and corresponding allele-specific siRNA) would be needed to provide at least one treatment possibility for this percentage of patients. By computing all combinations, we found that a repertoire of allele-specific siRNA corresponding to seven sites can provide at least one allele-specific siRNA treatment option for 85.6% of our sample. Moreover, we provide evidence that allele-specific siRNA targeting these sites are readily identifiable using a high throughput screening method, and that allele-specific siRNA identified using this method indeed show selective suppression of endogenous mutant htt protein in fibroblast cells from HD patients. Therefore, allele-specific siRNA are not so rare as to be impractical to find and use therapeutically.

To the Editor:Mowatetal.[1998]describedaseriesofsixisolatedpatients with microcephaly, mental retardation,and a peculiar facial phenotype. Five patients hadHirschsprung disease (HSCR) [Mowat et al., 1998].The disorder, which was designated by the eponymMowat–Wilson syndrome (MWS, OMIM #235730),was demonstrated to be caused by heterozygousmutations in the Zinc finger E-box-Binding homeo-box 2 gene (ZEB2, also known as ZFHX1B orSMADIP1) [Cacheux et al., 2001; Wakamatsu et al.,2001;Yamadaetal.,2001].Molecularanalysishelpedto delineate the cardinal features of MWS (facialgestalt and delayed psychomotor development)as well as several variably associated congenitalanomalies, including HSCR, agenesis of the corpuscallosum, seizures, eye anomalies, heart malforma-tions, genital, and urinary tract defects [reviewed byAdam et al., 2006; Garavelli and Mainardi, 2007].To date, there are approximately 180 mutation-positivepatientswithMWSintheliterature,with100different ZEB2 mutations reported [Zweier et al.,2005]. Three cases of recurrence in siblings havebeen reported [McGaughran et al., 2005; Zweieret al., 2005; Ohtsuka et al., 2008]. We describe twosisters with clinical features of MWS in whom thesame nonsense mutation in the ZEB2 gene wasfound.Theoldersiblingisnow6yearsold.Shewasbornby spontaneous delivery at 39 weeks of gestation.Antenatalscanningperformedat20weekssuggestedagenesis of the corpus callosum. Birth weight was3,670g(75thcentile),lengthwas52cm(75thcentile).Head circumference at birth was not measured.Hypotonia and feeding difficulties were present inthe neonatal period. Growth was normal. Psycho-motor development was delayed: she walked at30monthsofageandstillpronounces4–5words.At18 months an episode of febrile seizures occurred,followed by afebrile tonic-clonic seizures treatedwith valproate. Postnatal cerebral MRI confirmedagenesisofthecorpuscallosum.Ultrasoundscansoftheheartandabdomenandkaryotypewerenormal.Constipation was never reported. The clinicaldiagnosis of MWS was first raised when she was5 years of age by the presence of her facial gestalt(Fig. 1A–C). Length was 112 cm (50–75th centile),weight18kg(25thcentile),headcircumferencewas51 cm (50th centile).The sister was born at 39 weeks of gestation byspontaneous delivery. Again probable agenesis ofthe corpus callosum was noted on the antenatalultrasound scan (20th week of gestation). At birthweight was 4,010 g (90th centile), length 52 cm(75th centile), head circumference was not meas-ured. Echocardiography on day 3 revealed a com-plex heart malformation: aortic coarctation andvalvularstenosis,pulmonaryvalvestenosis,multiple

The molecular diagnosis of fragile X syndrome relies on the detection of the pathogenic CGG repeat expansion in the FMR1 gene. Deletions and point mutations have occasionally been reported. Rare polymorphisms might mimic a deletion by Southern blot analysis, leading to false-positive results. We describe a novel rare nucleotide substitution within the CGG repeat. The proband was a woman with a positive family history of mental retardation. Southern blot analysis showed an additional band consistent with a deletion in the region detected by the StB12.3 probe. Sequencing of this region revealed a G>C transversion that interrupts the CGG repeat and introduces an EagI site. The same variant was observed in both the healthy son and father of the proband, supporting the hypothesis that the nucleotide substitution is a silent polymorphism, the frequency of which we estimated to be less than 1% in the general population. These findings argue for a pathogenic role of nucleotide variants within the CGG repeat and suggest possible consequences of unexpected findings in the molecular diagnostics of fragile X syndrome. Thus, although the sequence context of a single nucleotide substitution may not predict possible effects on mRNA or protein function, a specific change in the higher order structures of DNA or mRNA may be functionally relevant in the pathological phenotype.

Department of Neuroscience, Ophthalmology and Genetics, University of Genova, Department of Mental Health, ASL3 ‘Genovese’, Genova, Genetic Unit, Psychiatric Rehabilitation Center, IRCCS ‘San Giovanni di Dio’, Fatebenefratelli, Brescia and Biology and Genetics Division, Department of Biomedical Sciences and Biotechnologies, Brescia University School of Medicine, Brescia, Italy Correspondence to Emilio Di Maria, MD, PhD, Department of Neuroscience, Ophthalmology and Genetics, University of Genova, Via De Toni 5, 16132 Genova, Italy Tel: + 39 0103538980; fax: + 39 0103538978; e-mail: emilio.dimaria@unige.it

Von Hippel-Lindau (VHL) disease is a rare autosomal dominant disorder characterized by multifocal and bilateral renal cell carcinoma and cysts, retinal angiomas, hemangioblastoma of the central nervous system, pheochromocytoma, epididymis cystoadenoma, pancreatic cysts and/or islet cell tumors. However, phenotypic manifestations and clinical outcome are wide ranging including inter and intra-familial patterns. The VHL gene has been localized on chromosome 3 p 25-26 and more than 250 germline mutations have been described. The sensitivity of analytic techniques of VHL gene is close to 100%. It is well known that about 25% of VHL patients present de novo mutations, and first cases function as possible founders of new VHL kindreds. Herein, we report the clinical case of a 45-year-old Caucasian female patient affected by bilateral polycystic kidney disease with two renal carcinomas in both kidneys without lynphoadenopathies. She underwent ophthalmologic surgery at 19 years old because of retinal detachment due to bilateral retinal angiomatosis. Direct gene sequencing showed a deletion-insertion in exon 3, starting from nucleotide 499 of the coding sequence (c.499-504 delinstT) in a heterozygous status; it causes a frame-shift and creates a premature stop at codon 170. The genetic study of the unaffected parents and of the unaffected brother confirmed the diagnosis of de novo VHL disease with the dentification of a new germline mutation, never reported in the literature. The patient showed normal kidney function and she did not show other organ lesions or clinical manifestations of VHL disease. She was successfully submitted to renal parenchymal sparing-surgery. In conclusion, it is important to test for germline mutations in VHL patients with the involvement of one organ or a pair of organs. Once the mutation is found in the proband, all family members can be easily tested for the documented mutation. The early identification of VHL patients is very important for clinical and genetic reasons.

Von Hippel-Lindau (VHL) disease is an autosomal dominant syndrome characterized by germline mutations in the VHL tumor suppressor gene located at chromosome 3p25-26 and pleomorphic clinical picture. The major clinical manifestations include retinal angiomas, central nervous system hemangioblastomas, pheopleochromocytoma, pancreatic cysts, epididymal cystoadenomas and renal lesions. Recently, we observed a 58-year-old male patient with macrohematuria and a history of nephrectomy due to renal cell carcinoma (RCC). The patient showed retinal angiomatosis, cerebellar hemangioblastomas, multiple pancreatic cysts, right kidney with polycystic features plus two RCC. The patient's offspring, two females and one male, showed VHL lesions, such as retinal angiomatosis, cerebellar hemangioblastomas and polycystic kidney disease (PKD). The affected family members were screened for mutations in the VHL gene. Data suggested the presence of a deletion encompassing exon 1 of the VHL gene. Early diagnosis of VHL disease in patients and their relatives is important for clinical and geneticreasons. VHL disease patients have an increased incidence of malignant carcinomas and the syndrome can mimic the presentation of other cystic kidney diseases. Early diagnosis and molecular genetic testing of family members is essential to improve the clinical management of patients and to allow an accurate risk assessment in asymptomatic individuals. In conclusion, nephrologists and urologists must carefully evaluate patients with PKD and RCC to confirm or exclude VHL disease, and physicians must play a crucial role in the clinical process of therapeutical decisions and choices for VHL patients.

A well established model for the pathophysiology of schizophrenia postulates a role for the NMDA-mediated glutamate transmission. The human gene coding for the 2B subunit of the NMDA receptor (GRIN2B) is considered a candidate based on its selective expression in brain. To evaluate the hypothesis that GRIN2B acts as a major gene in determining susceptibility to schizophrenia, a case-control association study was performed. Five single nucleotide polymorphisms (SNPs) were genotyped in 188 Italian patients and 156 control subjects. The association study showed a marginally significant excess of homozygosity for the polymorphism located in the 3'UTR region (P = 0.04). No other difference in genotype and allele frequencies was found in schizophrenics as compared to the control series. The case-control study was also carried out on estimated haplotypes, confirming a trend for association (P = 0.04). These results suggest that GRIN2B variations might be linked with susceptibility to schizophrenia. Replication studies on larger samples are warranted to further test this hypothesis.