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A 45-year-old Italian male was referred as suspected of having a heritable connective tissue disorders by clinical findings, including joint hyperlaxity and soft, smooth, velvety, and slightly elastic skin. Using a specific custom panel including genes involved in these disorders, next-generation sequencing (NGS) analysis led to the identification of the c. 5443G>A, p.(Gly1815Ser), (rs745680336) variant in fibrillin-1 (FBN1) gene, encoding the FBN1. Mutations in this protein are responsible for different connective tissue disorders, collectively known as type 1 fibrillinopathies, including Marfan syndrome (MFS). Multiple sequencing alignment of human FBN1 protein with various species revealed that the mutation occurred within a highly conserved region of the calcium-binding epidermal growth factor-like domain and affected the protein structure/function, suggesting its pathogenic role. NGS techniques successfully identified the molecular defect in this patient, clinically resembling as MFS, even if a clear genotype-phenotype correlation remains still challenging.

Ehlers-Danlos syndrome (EDS) is a clinically and genetically heterogeneous group of heritable connective tissue disorders (HCTDs) defined by joint laxity, skin alterations, and joint hypermobility. The latest EDS classification recognized 13 subtypes in which the clinical and genetic phenotypes are often overlapping, making the diagnosis rather difficult and strengthening the importance of the molecular diagnostic confirmation. New genetic techniques such as next-generation sequencing (NGS) gave the opportunity to identify the genetic bases of unresolved EDS types and support clinical counseling. To date, the molecular defects have been identified in 19 genes, mainly in those encoding collagen, its modifying enzymes or other constituents of the extracellular matrix (ECM). In this review we summarize the contribution of NGS technologies to the current knowledge of the genetic background in different EDS subtypes

Alzheimer's disease (AD) is a heterogeneous neurodegenerative disorder and represents the most common form of senile dementia. The pathogenesis of AD is not yet completely understood and no curative treatment is currently available. With the recent advancement in transcriptome-wide profiling approach, several non-coding RNAs (ncRNAs) have been identified. Among them, long non-coding RNAs (lncRNAs), which are long transcripts without apparent protein-coding capacity, have received increasing interest for their involvement in a wide range of biological processes as regulatory molecules. Recent studies have suggested that lncRNAs play a role in AD pathogenesis, although their specific influences in the disorder remain to be largely unknown. Herein, we will summarize the biology and mechanisms of action of the best characterized dysregulated lncRNAs in AD, focusing the attention on their potential role in the disease pathogenesis. A deeper understanding of the molecular mechanisms and the complex network of interactions in which they are implicated should open the doors to new research considering lncRNAs as novel therapeutic targets and prognostic/diagnostic biomarkers.

The Ehlers-Danlos syndromes (EDS) comprise a clinically and genetically heterogeneous group of heritable connective tissue disorders (HCTDs), characterised by joint hypermobility, hyperextensibility of the skin and tissue fragility that can induce symptoms from multiple organ systems. The latest EDS nosology distinguished thirteen subtypes with an overlap of phenotypic features, making the clinical diagnosis rather difficult and highlighting the importance of molecular diagnostic confirmation. Although the nervous system is not considered a primary target of the underlying molecular defect, recently, increasing attention has been focused on neurological manifestations of EDS. Among them, epilepsy represents a frequent cause of morbidity in these syndromes and can influence the long-term evolution of these patients, but the mechanisms are needed to be clarified. The aim of this review is to give a comprehensive overview and to analyze a possible association between EDS and epilepsy, focusing on the various brain anomalies and the types of epilepsy reported in patients affected by EDS.

Two hundred and fifty one Italian patients with sporadic frontotemporal lobar degeneration (FTLD) and 259 age-matched controls were tested for association with the tagging single nucleotide polymorphisms (SNPs) rs741810 and rs1052352 in the fused in sarcoma/translated in liposarcoma gene (FUS/TLS). Only patients negative for GRN mutations were included. Considering each SNP alone, no differences in either allelic or genotypic frequencies between patients and controls were found (P > 0.05), even stratifying according to gender or the presence of concomitant motor neuron disease. Haplotype analysis failed to detect haplotypes associated with FTLD. According to these results, FUS/TLS is not a susceptibility factor for the development of sporadic FTLD. © 2010-IOS Press and the authors. All rights reserved.

Mutations in the progranulin gene (GRN) are responsible for familial FTLD with ubiquitin pathology (FTLD-U). However, there are controversial data regarding the contribution of GRN variability to sporadic FTLD. We carried out an association study in 265 patients, who did not carry a GRN causal mutation, and 375 age-matched controls. Four tagging Single Nucleotide Polymorphisms (SNPs) were chosen generate 80% power to detect an allelic association with P ≤ 0.01. In addition, a known functional SNP (rs5848) was included. An increased frequency of the rs4792938 CC genotype in cases compared with controls was observed (17.4 versus 10.4%, P=0.01, OR: 1.81, 95%CI: 1.15-2.85). Stratifying for gender, no differences were observed for all polymorphisms. Haplotype analysis failed to detect haplotypes associated with the disease. Our findings indicate that the GRN rs4792938 CC genotype represents a susceptibility factor for the development of FTLD in individuals who do not carry GRN causal mutations. This SNP is likely located in a regulatory region, thus an effect on GRN mRNA levels may be of mechanistic importance. © 2010 - IOS Press and the authors. All rights reserved.

Linkage analysis identified a region on chromosome 9p associated with Frontotemporal Lobar Degeneration (FTLD). A detailed analysis of candidate genes lying in this region demonstrated an association with Ubiquitin Associated Protein (UBAP)1. The distribution of five Single Nucleotide Polymorphisms (SNPs) located in the chromosome 9 haplotype identified via linkage analysis, including UBAP1 rs7018487, UBAP2 rs1785506 and rs307658, and KIF24 rs17350674 and rs10814083, has been determined in a population of 284 patients diagnosed with FTLD, including 245 with behavioural variant Frontotemporal Dementia (bvFTD), 23 with Progressive Aphasia and 16 with Semantic Dementia, compared with 318 age-matched controls. A statistically significant increased frequency of the KIF24 rs17350674 AA genotype was observed in patients compared with controls (7.4 versus 2.5%; P= 0.0068, OR: 3.63, CI: 1.58-8.35). Considering each syndrome separately, similar results where obtained in bvFTD versus controls (7.7 versus 2.5%, P= 0.005, OR: 3.26, CI: 1.40-7.57). Stratifying for gender, a statistically significant increased genotypic frequency was observed in female patients as compared with female controls (8.9 versus 2.5%, P= 0.008, OR: 3.85, CI: 1.36-10.93). In silico analysis predicted that the substitution from W to L caused by the rs17350674 affects protein function (P< 0.05). The KIF24 rs17350674 polymorphism likely acts as a risk factor for sporadic FTLD, but a replication study would be needed to confirm these preliminary findings. © 2010 Elsevier Ireland Ltd.

Semaphorins of the Sema IV family are expressed in neurons and decreased in brains from patients with Alzheimer's disease (AD). Accumulation of an internalized form of Sema3A is associated with degeneration of neurons, making these molecules candidates for the development of AD. Single nucleotide polymorphisms (SNPs) rs36026860 and rs28469467 in Sema3A as well as rs13284404 and rs11526468 in Sema4D were analyzed in a population of 240 patients with AD compared with 222 age-matched controls. None of SNPs in Sema3A were present, either in patients or controls. The distribution of the Sema4D rs11526468 and rs13284404 SNPs was not significantly different between patients and controls, even stratifying for gender or age at onset. In silico analysis predicted that rs11526468 and rs28469467 are probably damaging. This high degree of conservation of Sema3A suggests a very important role for this protein. However, neither Sema3A nor Sema4D likely influence the susceptibility to AD. © Springer-Verlag 2009.

Three single nucleotide polymorphisms (SNPs) with a potential impact on the function of selectins (rs6133, rs4987310 and rs5368 substitutions localized in the coding regions of P-sel, L-sel and E-sel, respectively) were analyzed in an Italian population of 165 patients with multiple sclerosis (MS) as compared with 149 controls and in a replication American population of Caucasian descent consisting of 122 patients and 50 controls. No significant differences in either allelic or genotypic frequency in all the SNPs tested were found in the Italian population. A tendency to an increased frequency of the rs6133 T allele was observed in the American population, but applying the Bonferroni correction the significance threshold was not reached. Haploview analysis demonstrated that rs4987310 and rs5368 markers are in strong LD (D′ = 0.97) in both populations. Combining the two SNPs, we found no difference in haplotype distribution in patients compared with controls, either in Italian or in American population. Despite the fact that selectins play a role in the pathogenesis of MS and their encoding genes are located in regions associated with the disease, the selectin gene cluster studied likely does not influence the susceptibility to MS in Caucasians. © 2009 Springer-Verlag.

Background and purpose: Frontotemporal lobar degeneration (FTLD) is considered as a proteinopathy; therefore, it is conceivable that genes encoding for factors involved in protein misfolding and/or degradation could play a role in its pathogenesis. Methods: An association study of defective in cullin neddylation 1 (DCN-1)-domain containing 1 (DCUN1D1), which is involved in protein degradation, was carried out in a population of 220 patients with FTLD as compared with 229 age-matched controls. Results: A statistically significant increased frequency of the GG genotype of the DCUN1D1 rs4859146 single nucleotide polymorphism (SNP) was observed in patients compared with controls (6.9 vs. 1.7%, P = 0.011, adjusted OR: 4.39, 95% CI: 1.40-13.78). Stratifying according to the clinical syndrome, significant differences were observed between the behavioral variant of frontotemporal dementia and controls (GG frequency: 6.3 vs. 1.7%, P = 0.02, OR:4.0, 95%, CI = 1.24-12.92), as well as between patients with progressive aphasia compared with controls (15.4 vs. 1.7%, P = 0.014, OR = 11.30, 95%, CI = 1.63-78.45), but not in patients with SD versus controls (8.3 vs. 1.7%, P = 0.18, OR = 5.24, 95% C.I. = 0.45-60.63). No significant differences in allelic and genotypic frequencies of the DCUN1D1 rs4859147 SNP were found. Conclusions: The GG genotype of the DCUN1D1 rs4859147 SNP represents a risk factor for the development of FTLD, increasing the risk of about fourfold. © 2009 EFNS.

CCL2/Monocyte Chemoattractant Protein (MCP)-1 and other chemokines sharing a similar sequence, including CCL8/MCP-2, are involved in neurodegeneration. A few Single Nucleotide Polymorphisms (SNPs) have been reported in CCL8/MCP-2, all of which are located in the same linkage block. One of them (rs1163763) leads to an aminoacidic substitution, implying a potential impact on the function of the protein. rs1133763 was tested for association in 219 patients with Alzheimer's disease (AD) and 209 with Frontotemporal Lobar Degeneration (FTLD) as compared with 231 age-matched controls. The distribution of CCL8/MCP-2 rs1133763 was not significantly different among patients with AD or FTLD and controls, even stratifying according to gender. CCL8/MCP rs1133763 SNP, or other variants in linkage disequilibrium with this variant, likely do not influence the susceptibility to AD or FTLD in Caucasians. © 2009 Springer-Verlag.

Background and aims: Neuronal nitric oxide synthase (NOS)1 C276T polymorphism was shown to increase the risk for frontotemporal lobar degeneration (FTLD). In the brain, both NOS1 and NOS3 (endothelial isoform) have been detected. The distribution of NOS3 G894T (Glu298Asp) and T-786C single nucleotide polymorphisms (SNPs) was analyzed in a population of 222 patients with FTLD compared with 218 age-matched controls to determine whether they could influence the susceptibility to develop the disease. Results: A statistically significant increased frequency of the NOS3 G894T SNP was observed in patients as compared with controls (40.0 vs. 31.4%, P = 0.011, OR: 1.65, CI: 1.13-2.42). Conversely, the distribution of the T-786C SNP was similar in patients and controls. No differences were observed stratifying according to gender. Discussion: The NOS3 G894T polymorphism likely acts as risk factor for sporadic FTLD, but studies in larger populations are needed to confirm these preliminary findings. © 2008 EFNS.

Mutations in the progranulin gene (GRN), causative for Frontotemporal Lobar Degeneration with ubiquitin-immunoreactive neuronal inclusions (FTLD-U), could also be associated with Alzheimer's disease (AD). The influence of GRN genetic variability on susceptibility to AD and on expression levels in a series of neuropathologically-confirmed AD patients as well as in peripheral mononuclear cells (PBMC) and in cells isolated from cerebrospinal fluid (CSF) was investigated. An association study of rs9897526 and rs5848 was carried out in an Italian population and in a replication population of European American patients and controls. None of the variants tested act as unequivocal susceptibility factor in both populations although rs9897526 anticipated the onset of the disease in the Italian population. GRN expression in the parietal lobe of AD cases showed a 0.76-fold decrease compared with controls (1.31 ± 0.07 versus 1.73 ± 0.12, P = 0.0025). Patients carrying the rs5848 TT genotype had the lowest GRN expression levels (0.96 ± 0.12, P = 0.014). Despite no significant differences were found in the relative PBMC and CSF GRN expression in patients compared to controls, stratifying patients according to the presence of rs5848 T allele, a 0.57-fold decrease in GRN mRNA levels over C carriers was found in PBMC (1.22 ± 0.23 versus 0.70 ± 0.12, P = 0.04). Similarly to data obtained in brain samples, patients carrying the TT genotype showed the lowest GRN mRNA levels (TT = 0.46 ± 0.14, CC = 1.22 ± 0.23; P = 0.013). These data argue against a direct role of GRN as a susceptibility factor for sporadic AD but support a role of GRN as a disease-modifying gene, possibly contributing to the failure of neuronal survival. © 2009-IOS Press.

Background and purpose: Progranulin (PGRN) expression is increased in activated microglia in Alzheimer's disease (AD) brain, suggesting a potential role in this pathology. Methods: A mutation scanning of exons and flanking regions of PGRN was carried out in 120 patients with sporadic frontotemporal lobar degeneration and 145 with sporadic AD. Results: Amongst variants not yet deposited, a novel allelic variant was identified in Exon 1 (g100169G > A). It leads to an amino acidic change (p.Gly35Arg) and was observed in a patient with late onset AD. In silico analysis predicted that this mutation is possibly damaging. A second variant (g.100165C > T), resulting in a silent mutation (pAsp33Asp), was found in a patient with semantic dementia and in another with early onset AD. Both variants were absent in 226 controls. In addition, two rare non-pathogenic variants lying very close to PGRN splice-site regions (IVS2 + 7→G > A and IVS7 + 7→G > A) were observed. Transcriptional analysis in peripheral blood mononuclear cells from patients demonstrated they do not affect exon splicing. Conclusions: A novel putative PGRN mutation leading to an amino acidic substitution was identified in a patient with clinical AD. © 2008 The Author(s).

The neuronal nitric oxide synthase (nNOS) is abundantly expressed in the brain and its transcripts have been found in the frontal cerebral cortex. Eighty-nine patients with different neurodegenerative tau-related disorders, including 71 patients with frontotemporal lobar degeneration (FTLD), 12 with progressive supranuclear palsy (PSP) and 6 with corticobasal degeneration (CBD), were genotyped for the C276T single nucleotide polymorphism (SNP) in exon 29 of the nNOS gene and compared with 190 age-matched controls (CON). A significantly increased allelic frequency of the T allele was observed in patients compared with CON (40.4% vs. 29.7%, P = 0.014, OR: 1.94, CI: 1.15-3.27). Considering each disorder separately, significance was reached for FTLD only (39.4%, P = 0.0248 versus controls, OR: 1.96, CI: 1.11-3.47). However, the frequency of the T allele was elevated also in patients with PSP (45.8%) and CBD (41.7%). No differences were observed stratifying according to gender or apolipoprotein E status. The C276T SNP acts as risk factor for sporadic FTLD, possibly influencing NOS1 transcription. Studies in larger populations are needed to confirm its role in PSP and CBD. © 2007 The Author(s).

Recently, proteomic analysis in cerebrospinal fluid (CSF) from patients with MS identified four proteins which are present in MS but not in normal human CSF, including SPARCL1, an extracellular matrix-associated protein member of the SPARC family. One hundred eighty-six patients with MS and 185 age-matched controls were genotyped for A/G single nucleotide polymorphism (SNP) in exon 1 (rs1049539), C/G SNP in exon 4 (rs1049544), resulting in a substitution of an aspartate with an histidine, and A/G substitution in the exon 5 (rs1130643), leading to the substitution of alanine with threonine. No significant differences in either allelic or genotypic frequency of the three SNPs were found (P > 0.05), even in stratifying MS patients according to the course of the disease. Stratifying according to gender, a trend towards a decreased frequency of the C/C genotype of the rs1049544 was observed in male patients as compared with male controls (30.2% versus 44.0%; P = 0.217). Despite proteomic studies in CSF from MS patients suggested an important role for SPARCL1 in the development of the disease, SPARCL1 gene does not appear to act as susceptibility factor for MS in the population investigated here. However, the frequency of the C/C genotype of rs1049544 was decreased in male patients, possibly conferring a lower risk of developing MS in male population. Further studies are needed to clarify this issue. © 2007 Elsevier Ireland Ltd. All rights reserved.