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Since 2008, several groups have reported a lot of dominant mutations in TARDBP gene as a primary cause of Amyotrophic lateral sclerosis (ALS). Mutations in TARDBP gene are responsible for 4-5% of familial ALS (fALS) and nearly 1% of sporadic ALS (sALS). To date, over 50 dominant mutations were found in TDP-43 in both familial and sporadic ALS patients, most of which were missense mutations in the C-terminal glycine-rich region. Herein, we describe the clinical and genetic analysis of an Italian non-familial ALS patient with a late onset and a rapid disease progression, which led to the discovery of a novel TARDBP mutation. After neurological evaluation, molecular investigation highlighted the heterozygous substitution in exon 6 of TARDBP gene (S379A), which has previously neither been described nor reported in the ALS database. Several evidences supported the S379A mutation as causative in our patient: (a) it was neither found in ExAC nor 1000G and it was absent in our database of control subjects; (b) the position of the mutation involves an evolutionarily highly conserved residue; (c) two different amino acid substitutions in the same 379 codon were already reported in Swedish and Italian fALS cases, supporting the critical role of this codon for the protein function. The identification of this novel mutation enlarges the number of TARDBP mutations in ALS patients. [ABSTRACT FROM AUTHOR]

Mutations in the Cu/Zn superoxide dismutase 1 (SOD1) gene have been reported to cause adult-onset autosomal dominant amyotrophic lateral sclerosis (FALS). In sporadic cases (SALS), de novo mutations in the SOD1 gene have occasionally been observed. All the SOD1 mutations are autosomal dominantly inherited with the exception of D90A. To date, in Italy, only two sporadic ALS cases carrying the D90A mutation have been reported in a homozygous state. We investigated for the presence of this mutation in 169 unrelated ALS patients from southern Italy. The genetic analysis revealed three ALS patients (1.8%) with mild phenotype carrying the homozygous D90A mutation. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a multifactorial disease characterized by the interplay of genetic and environmental factors. In the majority of cases, ALS is sporadic, whereas familial forms occur in less than 10% of patients. Herein, we present the results of molecular analyses performed in a large cohort of Italian ALS patients, focusing on novel and already described variations in ALS-linked genes. Our analysis revealed that more than 10% of tested patients carried a mutation in one of the major ALS genes, with C9orf72 hexanucleotide expansion being the most common mutation. In addition, our study confirmed a significant association between ALS patients carrying the ATNX -1 intermediate repeat and the pathological C9orf72 expansion, supporting the involvement of this risk factor in neuronal degeneration. Overall, our study broadens the known mutational spectrum in ALS and provides new insights for a more accurate view of the genetic pattern of the disease. • Genetics of ALS in southern Italy similar to most other populations. • Novel variants of unknown pathogenicity discovered. • Confirmation of a significant C9orf72/ATXN1 association. • Involvement of C9orf72 expansion as risk factor in neuronal degeneration. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to investigate the possible role of JAG1 gene mutations in modulating clinical features in patients with CADASIL-like phenotype which resulted negative for NOTCH3 gene mutations. Sixty-six CADASIL-like patients without NOTCH3 gene mutations were investigated for 5 out of 26 exons of the JAG1 gene, whose mutations were implicated in central nervous system vascular abnormalities. PCR was performed with primers specific for exons 3, 4, 13, 23 and 24 comprising the intron–exon boundaries. Amplicons were then analyzed by denaturing high performance liquid chromatography (DHPLC). The exons showing a variant DHPLC profile were directly sequenced. The sequence of exons 3, 4 and 23 revealed the presence of four already described polymorphisms in JAG1. 1001C/T (g.16015 C>T) in exon 4 was found in 9 patients, IVS23+18delT (g.33147 delT) in 29 patients, IVS3-15T/C (g.15852 T>C) in 17 patients, IVS2-43C/T (g.10532 C>T) in 1 patient; both the polymorphism 1001C/T and IVS3-15T/C were found in 3 patients. No mutations were found. These data demonstrate absence of correlation between mutations in specific JAG1 gene exons and clinical features in patients with CADASIL-like phenotype. [Copyright &y& Elsevier]

Background: Hyperekplexia also known as Startle disease is a rare neuromotor hereditary disorder characterized by exaggerated startle responses to unexpected auditory, tactile, and visual stimuli and generalized muscle stiffness, which both gradually subside during the first months of life. Although the diagnosis of Hyperekplexia is based on clinical findings, pathogenic variants in five genes have been reported to cause Hyperekplexia, of which GLRA1 accounts for about 80% of cases. Dominant and recessive mutations have been identified in GLRA1 gene as pathogenic variants in many individuals with the familial form of Hyperekplexia and occasionally in simplex cases. Case presentation: In the present study, we describe clinical and genetic features of two Italian siblings, one with the major and one with the minor form of the disease. DNA samples from the probands and their parents were performed by NGS approach and validated by Sanger sequencing. The analysis of the GLRA1 gene revealed, in both probands, compound heterozygous mutations: c.895C > T or p.R299X inherited from the mother and c.587C > A or p.D98E inherited from the father. Conclusions: Until now, these two identified mutations in GLRA1 have not been reported before as compound mutations. What clearly emerges within our study is the clinical heterogeneity in the same family. In fact, even though in the same pedigree, the affected mother showed only mild startle responses to unexpected noise stimuli, which might be explained by variable expressivity, while the father, showed no clear signs of symptomatology, which might be explained by non-penetrance. Finally, the two brothers have different form of the disease, even if the compound heterozygous mutations in GLRA1 are the same, showing that the same mutation in GLRA1 could have different phenotypic expressions and suggesting an underling mechanism of variable expressivity. [ABSTRACT FROM AUTHOR]

Neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA), Parkinson's, Alzheimer's, and Huntington's disease affect a rapidly increasing population worldwide. Although common pathogenic mechanisms have been identified (e.g., protein aggregation or dysfunction, immune response alteration and axonal degeneration), the molecular events underlying timing, dosage, expression, and location of RNA molecules are still not fully elucidated. In particular, the alternative splicing (AS) mechanism is a crucial player in RNA processing and represents a fundamental determinant for brain development, as well as for the physiological functions of neuronal circuits. Although in recent years our knowledge of AS events has increased substantially, deciphering the molecular interconnections between splicing and ALS remains a complex task and still requires considerable efforts. In the present review, we will summarize the current scientific evidence outlining the involvement of AS in the pathogenic processes of ALS. We will also focus on recent insights concerning the tuning of splicing mechanisms by epigenomic and epi-transcriptomic regulation, providing an overview of the available genomic technologies to investigate AS drivers on a genome-wide scale, even at a single-cell level resolution. In the future, gene therapy strategies and RNA-based technologies may be utilized to intercept or modulate the splicing mechanism and produce beneficial effects against ALS. [ABSTRACT FROM AUTHOR]

Epilepsy refers to a common chronic neurological disorder that affects all age groups. Unfortunately, antiepileptic drugs are ineffective in about one-third of patients. The complex interindividual variability influences the response to drug treatment rendering the therapeutic failure one of the most relevant problems in clinical practice also for increased hospitalizations and healthcare costs. Recent advances in the genetics and neurobiology of epilepsies are laying the groundwork for a new personalized medicine, focused on the reversal or avoidance of the pathophysiological effects of specific gene mutations. This could lead to a significant improvement in the efficacy and safety of treatments for epilepsy, targeting the biological mechanisms responsible for epilepsy in each individual. In this review article, we focus on the mechanism of the epilepsy pharmacoresistance and highlight the use of a systems biology approach for personalized medicine in refractory epilepsy. [ABSTRACT FROM AUTHOR]

l-2-Hydroxyglutaric aciduria ( l-2-HGA) is a neurometabolic disease characterized by the presence of elevated levels of 2-hydroxyglutaric acid in the plasma, cerebrospinal fluid and urine. Clinical features in this inherited condition consist of mental deterioration, ataxia and motor deficits with pyramidal and extrapyramidal symptoms and signs. l-2-HGA is caused by mutations in the l-2-HGDH gene which most probably encodes for a l-2-hydroxyglutarate dehydrogenase, a putative mitochondrial protein converting l-2-hydroxyglutarate to alphaketoglutarate. Here, we report a pathogenic nonsense mutation in the l-2-HGDH gene found for the first time in an Italian patient affected by l-2-HGA, reinforcing the previously described phenotype of this rare metabolic disease and confirming the data indicating that mutations in the l-2-HGDH gene cause l-2-HGA. [ABSTRACT FROM AUTHOR]

Abstract: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI–TOF–MS) has been applied to the analysis of a wide range of biomolecules. To date, there are two specific areas of application where MALDI–TOF–MS is viewed as impractical: analysis of low-mass analytes and relative quantitative applications. However, these limitations can be overcome and quantification can be routine. Increased levels of thymosin β4 (TB4) have been recently found in cerebrospinal fluid (CSF) from Creutzfeldt–Jakob disease (CJD) patients. Our objective was to apply a label-free quantitative application of MALDI–TOF–MS to measure TB4 levels in human CSF by adding the oxidized form of TB4 as an internal standard. The relative peak area or peak height ratios of the native TB4 to the added oxidized form were evaluated. Considering the relative peak area ratios, healthy individuals showed a mean value of 40.8±21.27ng/ml, whereas CJD patients showed high values with a mean of 154±59.07ng/ml, in agreement with the previous observation found in CJD patients. Similar results were obtained considering peak height ratios. The proposed method may provide a simple and rapid screening method for quantification on CSF of TB4 levels suitable for diagnostic purposes. [Copyright &y& Elsevier]

Abstract: Mutations in the SPG4 gene are the most common causes of hereditary spastic paraplegia (HSP) accounting for up to 40% of autosomal dominant (AD) forms and 12–18% of sporadic cases. The phenotype associated with HSP due to mutations in the SPG4 gene tends to be pure. There is increasing evidence, however, of patients with complicated forms of spastic paraplegia in which SPG4 mutations were identified. A cohort of 38 unrelated Italian patients with spastic paraplegia, of which 24 had a clear dominant inheritance and 14 were apparently sporadic, were screened for mutations in the SPG4 gene. We identified 11 different mutations, six of which were novel (p.Glu143GlyfsX8, p.Tyr415X, p.Asp548Asn, c.1656_1664delinsTGACCT, c.1688-3C>G and c.*2G>T) and two exon deletions previously reported. The overall rate of SPG4 gene mutation in our patients was 36.8% (14/38); in AD-HSP we observed a mutation frequency of 45.8% (11/24), in sporadic cases the frequency was 21.4% (3/14). Furthermore, we found a mutational rate of 22.2% (2/9) and 41.4% (12/29) in the complicated and pure forms, respectively. The results underlie the importance of genetic testing in all affected individuals. [Copyright &y& Elsevier]

Abstract: Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant inherited disorder characterized by recurrent sensory or motor dysfunction. In 85% of HNPP cases the genetic defect is a 1.4 Mb deletion on chromosome 17p11.2, encompassing the PMP22 gene. Point mutations in the PMP22 gene responsible for HNPP phenotypes are rare. We investigated a 17-years-old girl who led to our detecting a novel mutation in PMP22 gene. The mutation was also detected in her father and corresponded to a deletion of one tymidine at position 11 in exon2 (c.11delT). This novel mutation creates a shift on the reading frame starting at codon 4 and leads to the introduction of a premature stop at codon 6. [Copyright &y& Elsevier]

Abstract: Spastic paraplegia type 4 is caused by mutations in the gene that encodes spastin (SPG4), a member of the AAA protein family. A cohort of 34 unrelated Italian patients with pure spastic paraplegia, of which 18 displayed autosomal dominant inheritance and 16 were apparently sporadic, were screened for mutations in the SPG4 gene by denaturing high performance liquid chromatography. We identified a previously reported mutation in a sporadic patient with pure hereditary spastic paraplegia. We also identified eight unrelated patients with pure autosomal dominant hereditary spastic paraplegia carrying five novel mutations in the SPG4 gene (one missense mutation, c.1304 C>T; one nonsense mutation, c.807C>A; two frameshift mutations, c.1281dupT, c.1514_1515insATA; and one splicing mutation, c.1322-2A>C). The frequency for SPG4 mutations detected in autosomal dominant hereditary spastic paraplegia was 44.4%. This study contributes to expand the spectrum of SPG4 mutations in Italian population. [Copyright &y& Elsevier]

Abstract: Charcot–Marie-Tooth type 1A is caused by a 1.5Mb DNA duplication in the 17p12 chromosomal region encompassing the peripheral myelin protein 22 gene. In the present study, we compared the Real-Time PCR with the other methods currently used for the diagnosis of Charcot–Marie-Tooth. By using a combination of junction fragment PCR, analysis of microsatellite markers, and pulsed field gel electrophoresis, we identified 76 unrelated patients with 17p12 duplication. In these patients, junction fragment PCR detected 63% of cases of duplication, the microsatellite markers method revealed 74%, while the combined use of microsatellite markers and junction fragment PCR revealed 91% of cases of Charcot–Marie-Tooth type 1A. Pulsed field gel electrophoresis detected 100% of the cases with duplication, even in presence of atypical 17p12 duplication. Real-Time PCR detected 100% of the cases with Charcot–Marie-Tooth type 1A and was comparable to pulsed field gel electrophoresis. However, in contrast to pulsed field gel electrophoresis, Real-Time PCR does not need fresh blood, minimizes diagnosis time and cost, and thus can be easily used for the molecular diagnosis of Charcot–Marie-Tooth type 1A. [Copyright &y& Elsevier]

Mitochondrial impairment has been implicated in the pathogenesis of the amyotrophic lateral sclerosis (ALS). Furthermore, mitochondrial-specific polymorphisms were previously related to other neurodegenerative diseases, such as Parkinson, Friedreich and Alzheimer disease. To investigate if specific genetic polymorphisms within the mitochondrial genome (mtDNA) could act as susceptibility factors and contribute to the clinical expression of sporadic ALS (sALS), we have genotyped predefined European mtDNA haplogroups in 222 Italian patients with sALS and 151 matched controls. Individuals classified as haplogroup I demonstrated a significant decrease in risk of ALS versus individuals carrying the most common haplogroup, H (odds ratio 0.08, 95% confidence interval 0.04–0.4, p < 0.01). Further stratification of the dataset by sex, age and site of onset of disease and survival failed to reach significance for association.Our study provides evidence of the contribution of mitochondrial variation to the risk of ALS development in Caucasians. Further it may help elucidate the mechanism of the mitochondrial dysfunction detectable in ALS, and may be of relevance in development of strategies for the treatment of this disease. [Copyright &y& Elsevier]

Distal hereditary motor neuronopathy is a genetically and clinically heterogeneous disorder. To date, five loci, and their relative genes, have been mapped on chromosomes 7p14, 7q11, 9q34, 11q12 and 12q24, respectively. We describe an Italian family with autosomal dominant distal HMN starting at around 30 years of age with weakness and atrophy of distal leg muscles and pyramidal features. We performed genetic linkage analysis on chromosomes 7p14, 9q34, 11q12 and 12q24. Moreover we sequenced the genes mapped to 7q11 and 12q24.Negative LOD scores excluded linkage to 7p14, 9q34, and 11q12 chromosomes in our family. No mutations were found in genes mapped to 7q11 and 12q24.In addition, because of pyramidal features, we performed the linkage analysis to all the known loci for autosomal dominant hereditary spastic paraparesis. The analysis was negative thus excluding a complicated form of autosomal dominant hereditary spastic paraparesis. These data further confirm a genetic heterogeneity within inherited motor neuronopathy. [Copyright &y& Elsevier]

Autosomal recessive spinal muscular atrophy is caused by mutations in the survival motoneuron (SMN) gene. There are two nearly identical copies of this gene present on chromosome 5q13; however, only the telomeric copy of this gene is affected in spinal muscular atrophy. In this study, we describe a new method to detect SMN gene deletion by denaturing high-performance liquid chromatography, which is also simple to perform but is faster and more specific. (J Child Neurol 2003; 18:269-271). [ABSTRACT FROM AUTHOR]