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Background Charcot–Marie–Tooth disease (CMT) is a genetically and clinically heterogeneous group of inherited neuropathies. Monoallelic pathogenic variants in ATP1A1 were associated with axonal and intermediate CMT. ATP1A1 encodes for the catalytic α1 subunit of the Na+/ K+ ATPase. Besides neuropathy, other associated phenotypes are spastic paraplegia, intellectual disability, and renal hypomagnesemia. We hereby report the first demyelinating CMT case due to a novel ATP1A1 variant. Methods Whole-exome sequencing on the patient’s genomic DNA and Sanger sequencing to validate and confirm the segregation of the identified p.P600R ATP1A1 variation were performed. To evaluate functional effects, blood-derived mRNA and protein levels of ATP1A1 and the auxiliary β1 subunit encoded by ATP1B1 were investigated. The ouabain-survival assay was performed in transfected HEK cells to assess cell viability, and two-electrode voltage clamp studies were performed in Xenopus oocytes. Results The variant was absent in the local and global control datasets, falls within a highly conserved protein position, and is in a missense-constrained region. The expression levels of ATP1A1 and ATP1B1 were significantly reduced in the patient compared to healthy controls. Electrophysiology indicated that ATP1A1p.P600R injected Xenopus oocytes have reduced Na+/ K+ ATPase function. Moreover, HEK cells transfected with a construct encoding ATP1A1p.P600R harbouring variants that confers ouabain insensitivity displayed a significant decrease in cell viability after ouabain treatment compared to the wild type, further supporting the pathogenicity of this variant. Conclusion Our results further confirm the causative role of ATP1A1 in peripheral neuropathy and broaden the mutational and phenotypic spectrum of ATP1A1-associated CMT.

Comprehensive data on variant transthyretin amyloidosis polyneuropathy (ATTRv-PN) in Greece are lacking. We presently provide an overview of ATTRv-PN in Greece, focusing on unexplored non-endemic regions of the country. In total, we identified 57 cases of ATTRv-PN diagnosed over the past 25 years, including 30 from the island of Crete, an apparent endemic region. Patients carried 10 different TTR mutations (C10R; P24S; V30M; R34G; R34T; I68L; A81T; E89Q; E89K and V94A). Carriers of the common V30M mutation constituted 54.3 % of the cohort. A known founder effect for the V30M mutation was present on the island of Crete. Non-endemic cases identified outside the island of Crete are presently reported in more detail. The age of onset ranged from 25 to 77 years, with a mean of 51.1 years. A mean diagnostic delay of 3.2 years was observed. V30M patients had earlier onset and less cardiac involvement than patients carrying other mutations. Genotype-phenotype correlations were largely consistent with published data. We conclude that, with the exception of the Cretan cluster, ATTRv-PN is not endemic in the Greek population. This makes timely diagnosis more challenging, yet absolutely essential given the availability of therapies that can alter the long-term course of the disease.

Spinal muscular atrophy (SMA) is a rare and devastating disease. New disease-modifying treatments have recently been approved and early treatment has been related to a better outcome. In this context, several newborn screening (NBS) programs have been implemented. The aim of the study was to obtain a global overview on the current situation and perspectives on SMA NBS. We conducted a survey and contacted experts from 152 countries, from which we gathered 87 responses. We identified 9 SMA NBS programs that have so far detected 288 newborns with SMA out of 3,674,277 newborns screened. Funding, screening methods, organisation, and consent process were variable between SMA NBS programs. Many respondents pointed the lack of cost/benefit data as a major obstacle to SMA NBS implementation. In the next four years, our data suggest a 24% coverage of newborns from countries where a disease-modifying drug is available and 8,5% coverage in countries with no diseases-modifying drugs. The annual proportion of newborns to be screened in the coming years is expected to increase steadily. The experts expressed a strong need for the implementation of SMA NBS as means to improve care for patients with SMA.

Background Next-generation sequencing (NGS) represents a significant advancement in clinical genetics. However, its use creates several technical, data interpretation and management challenges. It is essential to follow a consistent data analysis pipeline to achieve the highest possible accuracy and avoid false variant calls. Herein, we aimed to compare the performance of twenty-eight combinations of NGS data analysis pipeline compartments, including short-read mapping (BWA-MEM, Bowtie2, Stampy), variant calling (GATK-HaplotypeCaller, GATK-UnifiedGenotyper, SAMtools) and interval padding (null, 50 bp, 100 bp) methods, along with a commercially available pipeline (BWA Enrichment, Illumina®). Fourteen germline DNA samples from breast cancer patients were sequenced using a targeted NGS panel approach and subjected to data analysis. Results We highlight that interval padding is required for the accurate detection of intronic variants including spliceogenic pathogenic variants (PVs). In addition, using nearly default parameters, the BWA Enrichment algorithm, failed to detect these spliceogenic PVs and a missense PV in the TP53 gene. We also recommend the BWA-MEM algorithm for sequence alignment, whereas variant calling should be performed using a combination of variant calling algorithms; GATK-HaplotypeCaller and SAMtools for the accurate detection of insertions/deletions and GATK-UnifiedGenotyper for the efficient detection of single nucleotide variant calls. Conclusions These findings have important implications towards the identification of clinically actionable variants through panel testing in a clinical laboratory setting, when dedicated bioinformatics personnel might not always be available. The results also reveal the necessity of improving the existing tools and/or at the same time developing new pipelines to generate more reliable and more consistent data.

Background: Systemic Sclerosis (SSc), also known as scleroderma, is an autoimmune rheumatic disease, which is clinically subdivided into two major subgroups; limited (lcSSc) and diffuse cutaneous scleroderma (dcSSc). Even though the SSc etiologies remains unclear, some HLA and non-HLA genetic variants have been associated with the disease. Aim: This study was designed to evaluate the associations between several HLA-related genetic variants and SSc in the Greek-Cypriot population. Methods: Forty-one SSc patients and 164 controls were genotyped at 18 selected single nucleotide polymorphisms (SNPs) using restriction fragment length polymorphism analyses, Sanger sequencing, and a multiplex SNaPshot minisequencing assay. Logistic regression analysis under the log-additive model was used to evaluate all possible associations between these SNPs and SSc; nominal statistical significance was assumed at p

// Lola Koniali 1 , * , Andreas Hadjisavvas 1 , 2 , * , Anastasia Constantinidou 3 , Kyproula Christodoulou 2 , 4 , Yiolanda Christou 5 , Christiana Demetriou 6 , Andreas S. Panayides 7 , Constantinos Pitris 8 , Constantinos S. Pattichis 7 , Eleni Zamba-Papanicolaou 2 , 5 and Kyriacos Kyriacou 1 , 2 1 Department of Electron Microscopy/Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus 2 The Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus 3 Medical School, University of Cyprus and the Bank of Cyprus Oncology Centre, Nicosia, Cyprus 4 Neurogenetics Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus 5 Neurology Clinic D, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus 6 Department of Primary Care and Population Health, University of Nicosia Medical School, Nicosia, Cyprus 7 Department of Electrical and Computer Engineering, School of Engineering, University of Cyprus, Nicosia, Cyprus 8 Department of Computer Science, University of Cyprus, Nicosia, Cyprus * These authors contributed equally to this work Correspondence to: Kyriacos Kyriacou, email: kyriacos@cing.ac.cy Keywords: breast cancer; brain metastases; risk factors; biomarkers Received: August 21, 2019 Accepted: January 04, 2020 Published: February 11, 2020 ABSTRACT Background: Brain metastasis (BM) is an increasingly common and devastating complication of breast cancer (BC). Methods: A systematic literature search of EMBASE and MEDLINE was conducted to elucidate the current state of knowledge on known and novel prognostic factors associated with 1) the risk for BCBM and 2) the time to brain metastases (TTBM). Results: A total of 96 studies involving institutional records from 28 countries were identified. Of these, 69 studies reported risk factors of BCBM, 46 factors associated with the TTBM and twenty studies examined variables for both outcomes. Young age, estrogen receptor negativity (ER-), overexpression of human epidermal factor (HER2+), and higher presenting stage, histological grade, tumor size, Ki67 labeling index and nodal involvement were consistently found to be independent risk factors of BCBM. Of these, triple-negative BC (TNBC) subtype, ER-, higher presenting histological grade, tumor size, and nodal involvement were also reported to associate with shorter TTBM. In contrast, young age, hormone receptor negative (HR-) status, higher presenting stage, nodal involvement and development of liver metastasis were the most important risk factors for BM in HER2-positive patients. Conclusions: The study provides a comprehensive and individual evaluation of the risk factors that could support the design of screening tools and interventional trials for early detection of BCBM.

Anoctamin 10 (ANO10), also known as TMEM16K, is a transmembrane protein and member of the anoctamin family characterized by functional duality. Anoctamins manifest ion channel and phospholipid scrambling activities and are involved in many physiological processes such as cell division, migration, apoptosis, cell signalling, and developmental processes. Several diseases, including neurological, muscle, blood disorders, and cancer, have been associated with the anoctamin family proteins. ANO10, which is the main focus of the present review, exhibits both scrambling and chloride channel activity; calcium availability is necessary for protein activation in either case. Additional processes implicating ANO10 include endosomal sorting, spindle assembly, and calcium signalling. Dysregulation of calcium signalling in Purkinje cells due to ANO10 defects is proposed as the main mechanism leading to spinocerebellar ataxia autosomal recessive type 10 (SCAR10), a rare, slowly progressive spinocerebellar ataxia. Regulation of the endolysosomal pathway is an additional ANO10 function linked to SCAR10 aetiology. Further functional investigation is essential to unravel the ANO10 mechanism of action and involvement in disease development.

Background This study aims to characterize SARS-CoV-2 mutations which are primarily prevalent in the Cypriot population. Moreover, using computational approaches, we assess whether these mutations are associated with changes in viral virulence. Methods We utilize genetic data from 144 sequences of SARS-CoV-2 strains from the Cypriot population obtained between March 2020 and January 2021, as well as all data available from GISAID. We combine this with countries’ regional information, such as deaths and cases per million, as well as COVID-19-related public health austerity measure response times. Initial indications of selective advantage of Cyprus-specific mutations are obtained by mutation tracking analysis. This entails calculating specific mutation frequencies within the Cypriot population and comparing these with their prevalence world-wide throughout the course of the pandemic. We further make use of linear regression models to extrapolate additional information that may be missed through standard statistical analysis. Results We report a single mutation found in the ORF1ab gene (nucleotide position 18,440) that appears to be significantly enriched within the Cypriot population. The amino acid change is denoted as S6059F, which maps to the SARS-CoV-2 NSP14 protein. We further analyse this mutation using regression models to investigate possible associations with increased deaths and cases per million. Moreover, protein structure prediction tools show that the mutation infers a conformational change to the protein that significantly alters its structure when compared to the reference protein. Conclusions Investigating Cyprus-specific mutations for SARS-CoV-2 can lead to a better understanding of viral pathogenicity. Researching these mutations can generate potential links between viral-specific mutations and the unique genomics of the Cypriot population. This can not only lead to important findings from which to battle the pandemic on a national level, but also provide insights into viral virulence worldwide.

Background Spastic ataxias (SAs) encompass a group of rare and severe neurodegenerative diseases, characterized by an overlap between ataxia and spastic paraplegia clinical features. They have been associated with pathogenic variants in a number of genes, including GBA2. This gene codes for the non-lysososomal β-glucosylceramidase, which is involved in sphingolipid metabolism through its catalytic role in the degradation of glucosylceramide. However, the mechanism by which GBA2 variants lead to the development of SA is still unclear. Methods In this work, we perform next-generation RNA-sequencing (RNA-seq), in an attempt to discover differentially expressed genes (DEGs) in lymphoblastoid, fibroblast cell lines and induced pluripotent stem cell-derived neurons derived from patients with SA, homozygous for the GBA2 c.1780G > C missense variant. We further exploit DEGs in pathway analyses in order to elucidate candidate molecular mechanisms that are implicated in the development of the GBA2 gene-associated SA. Results Our data reveal a total of 5217 genes with significantly altered expression between patient and control tested tissues. Furthermore, the most significant extracted pathways are presented and discussed for their possible role in the pathogenesis of the disease. Among them are the oxidative stress, neuroinflammation, sphingolipid signaling and metabolism, PI3K-Akt and MAPK signaling pathways. Conclusions Overall, our work examines for the first time the transcriptome profiles of GBA2-associated SA patients and suggests pathways and pathway synergies that could possibly have a role in SA pathogenesis. Lastly, it provides a list of DEGs and pathways that could be further validated towards the discovery of disease biomarkers.

The neuronal ceroid lipofuscinoses (NCLs), also known as Batten disease, are a group of autosomal recessive lysosomal storage disorders that are characterized by neurodegeneration, progressive cognitive decline, motor impairment, ataxia, loss of vision, seizures, and premature death. To date, pathogenic variants in more than 13 genes have been associated with NCLs. CLN6 encodes an endoplasmic reticulum non-glycosylated transmembrane protein, which is involved in lysosomal acidification. Mutations in CLN6 cause late-infantile juvenile NCL (JNCL) adult-onset NCL, and Kufs disease. Members from two available families with JNCL were clinically evaluated, and samples were collected from consenting individuals. The molecular investigation was performed by whole-exome sequencing, Sanger sequencing, and family segregation analysis. Furthermore, in silico prediction analysis and structural modeling of the identified CLN6 variants were performed. We report clinical and genetic findings of three patients from two Greek-Cypriot families (families 915 and 926) with JNCL. All patients were males, and the first symptoms appeared at the age of 6 years. The proband of family 926 presented with loss of motor abilities, ataxia, spasticity, seizure, and epilepsy. The proband of family 915 had ataxia, spasticity, dysarthria, dystonia, and intellectual disability. Both probands did not show initial signs of vision and/or hearing loss. Molecular analysis of family 926 revealed two CLN6 biallelic variants: the novel, de novo p.Tyr295Cys and the known p.Arg136His variants. In family 915, both patients were homozygous for the p.Arg136His CLN6 variant. Prediction analysis of the two CLN6 variants characterized them as probably damaging and disease-causing. Structural modeling of the variants predicted that they probably cause protein structural differentiation. In conclusion, we describe two unrelated Cypriot families with JNCL. Both families had variants in the CLN6 gene; however, they presented with slightly different symptoms, and notably none of the patients has loss of vision. In silico prediction and structural analyses indicate that both variants are most likely pathogenic.

BackgroundDistal hereditary motor neuronopathies (dHMN) are a group of genetic disorders characterised by motor neuron degeneration leading to muscle weakness that are caused by mutations in various genes. HMNJ is a distinct form of the disease that has been identified in patients from the Jerash region of Jordan. Our aim was to identify and characterise the genetic cause of HMNJ.MethodsWe used whole exome and Sanger sequencing to identify a novel genetic variant associated with the disease and then carried out immunoblot, immunofluorescence and apoptosis assays to extract functional data and clarify the effect of this novel SIGMAR1 mutation. Physical and neurological examinations were performed on selected patients and unaffected individuals in order to re-evaluate clinical status of patients 20 years after the initial description of HMNJ as well as to evaluate new and previously undescribed patients with HMNJ.ResultsA homozygous missense mutation (c.500A>T, N167I) in exon 4 of the SIGMAR1 gene was identified, cosegregating with HMNJ in the 27 patients from 7 previously described consanguineous families and 3 newly ascertained patients. The mutant SIGMAR1 exhibits reduced expression, altered subcellular distribution and elevates cell death when expressed.ConclusionIn conclusion, the homozygous SIGMAR1 c.500A>T mutation causes dHMN of the Jerash type, possibly due to a significant drop of protein levels. This finding is in agreement with other SIGMAR1 mutations that have been associated with autosomal recessive dHMN with pyramidal signs; thus, our findings further support that SIGMAR1 be added to the dHMN genes diagnostic panel.

The advancement of scientific and medical research over the past years has generated a wealth of experimental data from multiple technologies, including genomics, transcriptomics, proteomics, and other forms of –omics data, which are available for a number of diseases. The integration of such multisource data is a key component toward the success of precision medicine. In this paper, we are investigating a multisource data integration method developed by our group, regarding its ability to drive to clusters of connected pathways under two different approaches: first, a disease-centric approach, where we integrate data around a disease, and second, a gene-centric approach, where we integrate data around a gene. We have used as a paradigm for the first approach Huntington's disease (HD), a disease with a plethora of available data, whereas for the second approach the GBA2, a gene that is related to spastic ataxia (SA), a phenotype with sparse availability of data. Our paper shows that valuable information at the level of disease-related pathway clusters can be obtained for both HD and SA. New pathways that classical pathway analysis methods were unable to reveal, emerged as necessary “connectors” to build connected pathway stories formed as pathway clusters. The capability to integrate multisource molecular data, concluding to something more than the sum of the existing information, empowers precision and personalized medicine approaches.

Additional file 2: Table S2. EuroGentest and the European Society of Human Genetics, guidelines for the evaluation and validation of NGS applications.

Additional file 1: Table S1. TruSight Cancer (Illumina) target genes in alphabetical order.

Additional file 3: Figure S1. Sequencing and Mapping Evaluation. a. Number of reads and clusters generated per run. b Number of unmapped reads per sample and alignment method.

Additional file 9. Detailed commands and parameters used for data pre-processing, sequence alignment, post-alignment processing and variant discovery.

Additional file 7: Figure S3. Box plot of Matthew Correlation coefficient (MCC) comparisons per alignment, variant calling or padding method. Each dot represents one observation and horizontal bold lines denote median MCC values. Boxes extend from the 25th to the 75th percentile of each group’s distribution of values. Vertical extending lines (whiskers) denote the upper and lower adjacent values. Statistical analyses were performed using the non-parametric Kruskal-Wallis or one-way ANOVA tests.

Additional file 8: Figure S4. Box plot comparisons of False Positive Rates (FPR). Only statistically significant differences are shown. Each dot represents one observation and horizontal bold lines denote median FPR values. Boxes extend from the 25th to the 75th percentile of each group’s distribution of values. Vertical extending lines (whiskers) denote the upper and lower adjacent values. Statistical analysis was performed using the non-parametric Kruskal-–Wallis test.

Additional file 4: Table S3. Number of reads per sample and mapping tool.

Additional file 5: Table S4. Minimum, mean and maximum depth of coverage, per gene and alignment algorithm. Depth of coverage results upon NextSeq 500 High-Output kit 2x75 cycles and 2x150 cycles sequencing.

Additional file 6: Figure S2. Hierarchical clustering of the tools. The d, MCC, p, r and F1 values were used to perform hierarchical clustering analysis based on the Lance–Williams agglomerative hierarchical clustering algorithm, which at each stage recomputes dissimilarities between clusters.

Spastic ataxia (SA) is a group of rare neurodegenerative diseases, characterized by mixed features of generalized ataxia and spasticity. The pathogenetic mechanisms that drive the development of the majority of these diseases remain unclear, although a number of studies have highlighted the involvement of mitochondrial and lipid metabolism, as well as calcium signaling. Our group has previously published the GBA2 c.1780G &gt, C (p.Asp594His) missense variant as the cause of spastic ataxia in a Cypriot consanguineous family, and more recently the biochemical characterization of this variant in patients&rsquo, lymphoblastoid cell lines. GBA2 is a crucial enzyme of sphingolipid metabolism. However, it is unknown if GBA2 has additional functions and therefore additional pathways may be involved in the disease development. The current study introduces bioinformatics approaches to better understand the pathogenetic mechanisms of the disease. We analyzed publicly available human gene expression datasets of diseases presented with &lsquo, ataxia&rsquo, or &lsquo, spasticity&rsquo, in their clinical phenotype and we performed pathway analysis in order to: (a) search for candidate perturbed pathways of SA, and (b) evaluate the role of sphingolipid signaling pathway and sphingolipid metabolism in the disease development, through the identification of differentially expressed genes in patients compared to controls. Our results demonstrate consistent differential expression of genes that participate in the sphingolipid pathways and highlight alterations in the pathway level that might be associated with the disease phenotype. Through enrichment analysis, we discuss additional pathways that are connected to sphingolipid pathways, such as PI3K-Akt signaling, MAPK signaling, calcium signaling, and lipid and carbohydrate metabolism as the most enriched for ataxia and spasticity phenotypes.

Hereditary transthyretin amyloidosis (ATTR) is a hereditary, sensorimotor and autonomic neuropathy caused by deposits of mutated transthyretin (TTR). The commonest TTR mutation is V30M (ATTRV30M) with patients usually living for about 10 years after disease onset. Liver transplantation (LT) until recently was considered the standard treatment. This study aims to assess the frequency of CNS complications in post-LT patients from the Cypriot cohort. Epidemiological data were collected for all genetically confirmed ATTRV30M neuropathy patients diagnosed at CING since 1992, and CNS-associated symptoms were assessed and evaluated by two neurology specialists. Out of the 48 transplanted patients, 10 (20.8%) presented with a CNS complication. All patients had ocular involvement, mainly glaucoma (7/10). Eight presented with transient focal neurological episodes (TFNEs), with expressive dysphasia being reported by four of them. The mean time of TFNE-emergence was 16.6 years after the LT. Three died from cerebral hemorrhage. CNS complications in post-LT ATTRV30M patients are not rare and usually manifest themselves at a time that surpasses the mean time the patients would have survived without a LT. CNS involvement is associated with increased mortality, due to cerebral hemorrhage.

Alzheimer’s disease (AD) is the most common neurodegenerative disease, affecting the elderly at a high incidence. AD is of unknown etiology and currently, no cure is available. Present medication is restricted to treating symptoms; thus, a need exists for the development of effective remedies. Medicinal plants constitute a large pool, from which active compounds of great pharmaceutical potential can be derived. Various Salvia spp. are considered as neuroprotective, and here, the ability of Salvia fruticosa (SF) to protect against toxic effects induced in an AD cell model was partly assessed. Two of AD’s characteristic hallmarks are the presence of elevated oxidative stress levels and the cytotoxic aggregation of amyloid beta (Aβ) peptides. Thus, we obtained SF extracts in three different solvents of increasing polarity, consecutively, to evaluate (a) their antioxidant capacity with the employment of the free radical scavenging assay (DPPH•), of the ferric reducing ability of plasma assay (FRAP), and of the cellular reactive oxygen species assay (DCFDA) and (b) their neuroprotective properties against Aβ25–35-induced cell death with the use of an MTT assay. All three SF extracts showed a considerable antioxidant capacity, with the methanol (SFM) extract being the strongest. The results of the total phenolic and flavonoid contents (TPC and TFC) of the extracts and of the FRAP and the DCFDA assays showed a similar pattern. In addition, and most importantly, the dichloromethane (SFD) and the petroleum ether (SFP) extracts had an effect on Aβ toxicity, exhibiting a significant neuroprotective potential. To our knowledge, this is the first report of SF extracts demonstrating neuroprotective potential against Aβ toxicity. In combination with their antioxidant capacity, SF extracts may be beneficial in combating AD and other neurodegenerative diseases.

Background Pathogenesis and aetiology of systemic sclerosis (SSc) are currently unclear, thus rendering disease prognosis, diagnosis and treatment challenging. The aim of this study was to use paired skin biopsy samples from affected and unaffected areas of the same patient, in order to compare the proteomes and identify biomarkers and pathways which are associated with SSc pathogenesis. Methods Biopsies were obtained from affected and unaffected skin areas of SSc patients. Samples were cryo-pulverised and proteins were extracted and analysed using mass spectrometry (MS) discovery analysis. Differentially expressed proteins were revealed after analysis with the Progenesis QIp software. Pathway analysis was performed using the Enrichr Web server. Using specific criteria, fifteen proteins were selected for further validation with targeted-MS analysis. Results Proteomic analysis led to the identification and quantification of approximately 2000 non-redundant proteins. Statistical analysis showed that 169 of these proteins were significantly differentially expressed in affected versus unaffected tissues. Pathway analyses showed that these proteins are involved in multiple pathways that are associated with autoimmune diseases (AIDs) and fibrosis. Fifteen of these proteins were further investigated using targeted-MS approaches, and five of them were confirmed to be significantly differentially expressed in SSc affected versus unaffected skin biopsies. Conclusion Using MS-based proteomics analysis of human skin biopsies from patients with SSc, we identified a number of proteins and pathways that might be involved in SSc progression and pathogenesis. Fifteen of these proteins were further validated, and results suggest that five of them may serve as potential biomarkers for SSc.

Huntington disease (HD) is most prevalent among populations of western European descent and isolated populations where founder effects may operate. The aim of this study was to examine the epidemiology of HD in Cyprus, an island in southern Europe with extensive western European colonization in the past. All registered HD patients in the Cyprus, since 1994, were included. Detailed pedigrees and clinical information were recorded and maps, showing the geographic distribution of HD, were constructed. Requests for genetic testing were also examined. The project identified 58 clinically manifested cases of HD belonging to 19 families. The 16 families of Cypriot origin were concentrated in a confined geographical cluster in southeast Cyprus. In 2015, prevalence of symptomatic HD was 4.64/100 000 population, while incidence was 0.12/100 000 person-years. Prevalence displayed a marked increase during the past 20 years. Disease characteristics of HD patients were similar to those reported in western European populations. Lastly, the uptake of predictive and/or prenatal testing was limited. HD disease characteristics, incidence and prevalence in Cyprus were comparable to western European populations. Together with the geographical clustering observed, these results support the possibility for a relatively recent founder effect of HD in Cyprus, potentially of western European origin.

Neurodegeneration with brain iron accumulation (NBIA) comprises a group of rare genetic disorders characterized by progressive extrapyramidal and other neurological symptoms due to focal iron accumulation in the basal ganglia (Adidi et al., 2016). β-Propeller protein-associated neurodegeneration (BPAN) is the most recently identified subtype of NBIA caused by heterozygous variants in WDR45 (OMIM: *300526) at Xp11.23. We report the clinical neurophysiological and neuro-imaging findings of a new subtype of BPAN in a 6 year-old female patient, who was identified to have a large de novo WDR45 deletion who presented in the first year of life with early onset global developmental delay, severe cognitive impairment, generalized hypotonia and a corticosteroid responsive epileptic encephalopathy.

ObjectiveTo examine the effect of variants in genes encoding molecules that are implicated in leukocyte trafficking into the CNS on the development of MS.MethodsA total of 389 Greek MS cases and 336 controls were recruited by 3 MS centers in Cyprus and Greece. In total, 147 tagging single nucleotide polymorphisms across 9 genes encoding for P-selectin (SELP), integrins (ITGA4, ITGB1, and ITGB7), adhesion molecules (ICAM1, VCAM1, and MADCAM1), fibronectin 1 (FN1), and osteopontin (SPP1) were genotyped. The clinical end point of the study was diagnosis of MS according to the 2005 revised McDonald criteria. Permutation analysis was used for adjusting for multiple comparisons.ResultsOverall, 21 variants across SELP, ITGA4, ITGB1, ICAM1, VCAM1, MADCAM1, FN1, and SSP1 genes were each associated with MS (pperm < 0.05). The most significant were rs3917779 and rs2076074 (SELP), rs6721763 (ITGA4), and rs1250258 (FN1), all with a permutation p value of less than 1e-004.ConclusionsThe current study provides preliminary evidence that variants across genes encoding adhesion molecules, responsible for lymphocyte adhesion and trafficking within the CNS, are implicated in the risk of developing MS.

BACKGROUND: ATTRV30M amyloidosis is a lethal autosomal dominant sensorimotor and autonomic neuropathy caused by amyloid deposition composed of aggregated misfolded TTR monomers with the V30M mutation. The age of onset in patients with ATTRV30M varies in different foci and the mechanism behind it is still unknown. METHODS: The tertiary neurology center following all ATTRV30M patients in Cyprus was used to collect demographic data to estimate; prevalence, incidence, penetrance, anticipation, time from disease onset to diagnosis and transplantation. Ocular, cardiac and leptomeningeal involvement in transplanted patients was explored. Correlation of C1q tagging SNPs with age of disease onset was carried out. RESULTS: Prevalence and incidence for ATTRV30M neuropathy in Cyprus are 5.4/100,000 and 0.3/100,000 respectively. Mean age of onset is 40.6 years and anticipation is 8.3 years. Penetrance reaches 51% and 75% by the ages of 50 and 80 years respectively. In liver transplanted patients rates of ocular, cardiac and leptomeningeal involvement were estimated to be 60%, 20% and 16%, respectively. C1q polymorphisms correlated with age of disease onset. CONCLUSIONS: ATTRV30M neuropathy has a rising prevalence in Cyprus due to improved survival of patients. Late onset complications are becoming a major problem. Complement C1q appears to be a modifier in this disease.

CMT is the most common hereditary neuromuscular disorder of the peripheral nervous system with a prevalence of 1/2500 individuals and it is caused by mutations in more than 80 genes. LRSAM1, a RING finger ubiquitin ligase also known as TSG101-associated ligase (TAL), has been associated with Charcot-Marie-Tooth disease type 2P (CMT2P) and to date eight causative mutations have been identified. Little is currently known on the pathogenetic mechanisms that lead to the disease. We investigated the effect of LRSAM1 deregulation on possible LRSAM1 interacting molecules in cell based models. Possible LRSAM1 interacting molecules were identified using protein-protein interaction databases and literature data. Expression analysis of these molecules was performed in both CMT2P patient and control lymphoblastoid cell lines as well as in LRSAM1 and TSG101 downregulated SH-SY5Y cells.TSG101, UBE2N, VPS28, EGFR and MDM2 levels were significantly decreased in the CMT2P patient lymphoblastoid cell line as well as in LRSAM1 downregulated cells. TSG101 downregulation had a significant effect only on the expression of VPS28 and MDM2 and it did not affect the levels of LRSAM1. This study confirms that LRSAM1 is a regulator of TSG101 expression. Furthermore, deregulation of LRSAM1 significantly affects the levels of UBE2N, VPS28, EGFR and MDM2.

Background Systemic Sclerosis (SSc) is an autoimmune connective tissue rheumatic disease characterised by three main hallmarks; vasculopathy, immune system abnormalities and fibrosis. It is considered a multisystemic and heterogeneous disease as many organs of the body may be affected and symptoms vary among patients. Up to date, SSc is untreated and its etiology and pathogenesis remain unclear. Early prognosis and diagnosis of the disease are challenging. Objectives The aim of this study was to analyse the proteomic profile of SSc patients in order to gain insights into the mechanisms implicated in disease pathogenesis and also discover new biomarkers that would facilitate early prognosis, more accurate diagnosis and therapeutic targeting of SSc. Methods Human biopsies were obtained from ten affected and three non-affected skin areas of SSc patients and have been classified based on histological criteria. Biopsies were cryo-pulverised and proteins were extracted, purified, reduced, alkylated and digested by trypsin. Purified peptides were analysed on a Waters Synapt G2Si HDMS instrument operated in ion mobility mode using a UDMSE approach. Data were processed by the Progenesis QIp and functional annotation analysis was carried out using multiple bioinformatics resources. Results Proteomic analysis led to the identification and quantification of approximately 1500 non-redundant proteins per sample. About 400 of these proteins, including interferons and interleukins, are differentially expressed between affected and non-affected samples. Functional annotation analysis of these proteins showed that they are involved in multiple pathways including, antigen processing and presentation, complement, ubiquitin mediated proteolysis and Notch signalling, which are known to be associated with autoimmune diseases and fibrosis. Conclusions Using a Mass Spectrometry-based proteomic approach for the analysis of SSc human skin biopsies, we identified a number of proteins that might be involved in the development and pathogenesis of SSc. Interestingly, some of these proteins are differentially expressed in specific histological groups and thus could be considered as potential biomarkers for specific SSc stages. Acknowledgements This work has received support from the EU/EFPIA/Innovative Medicines Initiative Joint Undertaking PRECISESADS grant n° 115565, the Cyprus Institute of Neurology and Genetics and Universite catholique de Louvain. Disclosure of Interest None declared