Search

Several case reports have indicated hearing impairment (HI) in hereditary motor and sensory neuropathy (HMSN). Two detailed studies have confirmed this. However, they were conducted before recent advances in molecular genetics made the genetic localization of subtypes of HMSN possible. The aim of this study is to combine knowledge of molecular genetics with the hearing thresholds in HMSN.Pure tone thresholds from 97 unselected patients with HMSN were collected. DNA from all patients was analysed for the most common genotype: a duplication on chromosome no. 17 (17p11.2-12, HMSNIA).Overall HI, defined as hearing thresholds >/=25 dB in the better hearing ear (pure tone average for 0.5, 1, 2 and 4 kHz) was present in 25 patients (26%) , compared to 16% in the general population. Sixty-three patients (65%) had the duplication on chromosome no. 17 (HMSNIA). The prevalence of hearing thresholds >/=5 dB in HMSNIA was significantly higher than the corresponding prevalence in the general population (92% and 72%, respectively). For all higher thresholds, prevalences were not significantly higher in HMSNIA than in the population. Thirty (31%) patients did not have the duplication on chromosome no. 17 (unknown type of HMSN). In this group, the prevalences of hearing thresholds s 15, 25, 30, 35 and 40 dB were significantly higher than in the population (>/= 25 dB, 37% and 16%, respectively). In the group with an unknown type of HMSN the prevalence of average hearing thresholds >/= 25 dB was significantly greater amongst males than females. The remaining four patients had minor changes within the 17p11.2-region. In this group HI was present as well.For patients with the duplication on chromosome 17 (HMSN1A) hearing thresholds were only slightly worse than in the population in general, but there was a greater variation between patients. For male patients with an unknown type of HMSN, hearing thresholds were worse (a mild HI) than for males in general. The prevalence of all degrees of hearing thresholds for females with HMSN of unknown type corresponded to the prevalence in the general female population. The prevalence of HMSN1A was 65% in Zealand, Denmark. [ABSTRACT FROM AUTHOR]

Oysters (Ostreidae) play a pivotal role in the health and productivity of marine ecosystems. Their unique ability to filter water, provide habitat, and contribute to nutrient cycling has remained underused in many parts of Europe following the destruction of vast oyster beds in the 19th and 20th centuries. The burgeoning field of oyster restoration for aquaculture has recognized the potential of these bivalves in promoting ecosystem resilience and enhancing biodiversity. Restoring oysters to previous levels requires the establishment of ecological baselines that ideally take into account the long-term changes of animal behavior as well as the surrounding environment prior to significant human intervention, an extremely challenging task. Archaeological shell middens are invaluable baseline archives and provide exclusive insights into past ecosystems. Here, we use demographic information from over 2,000 analyzed European oyster ( Ostrea edulis ) shells dating from ~5,660 to 2,600 cal BCE (calibrated years BCE), the largest archaeological growth rate dataset of mollusks yet. Through the analysis of size as well as ontogenetic age, we decouple anthropogenic from environmental impacts throughout Denmark. Our data show definitive influence of oyster size-age structure through human harvesting during the Mid-Holocene, with older oysters in the Mesolithic (mean: 4.9 y) than the Neolithic (mean: 3.7 y), irrespective of changes in growth rate. Furthermore, we present the metrics for long-term sustainable harvesting of oysters across environmental and socioeconomic transitions, providing demographic targets for current oyster restoration projects and valuable context in mitigating the impact of modern climatic change., Competing Interests: Competing interests statement:The authors declare no competing interest.

Western Eurasia witnessed several large-scale human migrations during the Holocene 1-5 . Here, to investigate the cross-continental effects of these migrations, we shotgun-sequenced 317 genomes-mainly from the Mesolithic and Neolithic periods-from across northern and western Eurasia. These were imputed alongside published data to obtain diploid genotypes from more than 1,600 ancient humans. Our analyses revealed a 'great divide' genomic boundary extending from the Black Sea to the Baltic. Mesolithic hunter-gatherers were highly genetically differentiated east and west of this zone, and the effect of the neolithization was equally disparate. Large-scale ancestry shifts occurred in the west as farming was introduced, including near-total replacement of hunter-gatherers in many areas, whereas no substantial ancestry shifts happened east of the zone during the same period. Similarly, relatedness decreased in the west from the Neolithic transition onwards, whereas, east of the Urals, relatedness remained high until around 4,000 BP, consistent with the persistence of localized groups of hunter-gatherers. The boundary dissolved when Yamnaya-related ancestry spread across western Eurasia around 5,000 BP, resulting in a second major turnover that reached most parts of Europe within a 1,000-year span. The genetic origin and fate of the Yamnaya have remained elusive, but we show that hunter-gatherers from the Middle Don region contributed ancestry to them. Yamnaya groups later admixed with individuals associated with the Globular Amphora culture before expanding into Europe. Similar turnovers occurred in western Siberia, where we report new genomic data from a 'Neolithic steppe' cline spanning the Siberian forest steppe to Lake Baikal. These prehistoric migrations had profound and lasting effects on the genetic diversity of Eurasian populations., (© 2024. The Author(s).)

Background/aim: There is an increasing prevalence of chronic heart failure (HF). It is well known that patients with HF and disturbances in the potassium level have an increased mortality risk. The aim of this study was to investigate the prognosis of a second plasma-potassium measurement after an episode with hyperkalaemia on short-term mortality in patients with chronic HF., Methods and Results: From Danish national registers, 2,339 patients with chronic HF and hyperkalaemia (>4.6 mmol/L) at first potassium measurement within 14-365 days from concomitant treatment were identified. To be included, a second measurement was required within 6-30 days subsequent to the first measurement and the 60-day mortality was observed. Based on the second measurement, the patients were divided into five groups: <3.5 mmol/L (n = 257), 3.5-4.0 mmol/L (n = 709), 4.1-4.6 mmol/L (n = 1,204, reference), 4.7-5.0 mmol/L (n = 89) and >5.0 mmol/L (n = 80). To assess all-cause and cardiovascular mortality, we used the Cox regression model. The multivariable analysis showed that patients with potassium concentrations <3.5 mmol/L (hazard ratio (HR): 3.03; 95% CI: 2.49-3.70) and 3.5-4.0 mmol/L (HR: 1.81; 95% CI: 1.54-2.14) had a worse prognosis compared to the reference. We observed similar results when calculating the risk of cardiovascular mortality. A restricted cubic spline curve showed a U-shaped relationship between plasma-potassium and all-cause mortality., Conclusion: Patients with chronic HF and hyperkalaemia who became hypokalaemic after 6-30 days were associated with a higher 60-day all-cause and cardiovascular mortality compared to the reference. This also applied for patients with low normal potassium concentrations (3.5-4.0 mmol/L)., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: The probability of a pregnancy, live birth, stillbirth and abortion has never been assessed in women with neurofibromatosis 1 (NF1) in a large population-based study., Methods: We included 1006 women (15-49 years) registered with NF1 in the Danish National Patient Registry or followed in two national Centers for Rare Diseases and 10 020 women from the Danish population. Information on pregnancy outcomes was ascertained from health registries. Cumulative incidence, mean cumulative count, hazard ratios (HRs) and proportion ratios (PRs) with 95% CIs were calculated., Results: The cumulative incidence of a first pregnancy at age 50 years was slightly lower in women with NF1 (74%; 95% CI 70 to 77) than in population comparisons (78%; 95% CI 77 to 79). When all pregnancies were included, two pregnancies were expected per woman at age of 50 years, irrespective of a NF1 diagnosis. The hazard of a pregnancy did not differ between women with NF1 (HR 1.03; 95% CI 0.95 to 1.11) and the comparisons after adjustment for somatic and psychiatric disease. The proportion of pregnancies that resulted in a live birth was 63% (783/1252) among women NF1 and 68% (8432/12 465) among the comparisons, yielding a PR of 0.95 (95% CI 0.90 to 1.00). The proportions of stillbirths (PR 2.83; 95% CI 1.63 to 4.93) and spontaneous abortions (PR 1.40; 95% CI 1.09 to 1.79) were increased in women with NF1., Conclusions: A similar hazard for pregnancy was observed for women with NF1 and population comparisons after adjustment for potential medical consequences of NF1. However, women with NF1 experienced more spontaneous abortions and stillbirths., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

The aim of this study was to assess the risks of psychiatric disorders in a large cohort of 905 individuals with NF1 and 7614 population comparisons matched on sex and year of birth. The cohort was linked to the Danish Psychiatric Central Research Register to ascertain information on hospital contacts for psychiatric disorders based on the International Classification of Diseases version 8 and 10. The hazard ratio (HR) for a first psychiatric hospital contact was higher in girls (4.19, 95% confidence interval [CI] 1.81-9.69) and boys with NF1 (5.02, 95% CI 3.27-7.69) <7 years of age than in the population comparisons. Both sexes had increased HRs for developmental disorders, including attention deficit/hyperactivity disorders, autism spectrum disorders, and intellectual disabilities in childhood. Females with NF1 had also increased HRs for unipolar depression, other emotional and behavioral disorders, and severe stress reaction and adjustment disorders in early adulthood. The HRs for psychoses, schizophrenia, bipolar disorders, and substance abuse were similar in individuals with NF1 and the population comparisons. Finally, the cumulative incidence of a first hospital contact due to any psychiatric disorder by age 30 years was 35% (95% CI 29-41) in females and 28% (95% CI 19-37) in males with NF1. Thus, screening for psychiatric disorders may be important for early diagnosis and facilitation of appropriate and effective treatment in individuals with NF1., (© 2021 Wiley Periodicals LLC.)

Individuals with neurofibromatosis 1 (NF1) may have problems in managing the transition between childhood and adulthood, such as forming a relationship or finding a partner. We aimed to determine the association between NF1 and forming and ending marital or cohabiting relationships by comparing a large Danish population of adults with NF1 with population comparisons. In this population-based cohort study, we compared a population of Danish adults who were hospitalized for or with complications to prior diagnosed NF1 (n = 787) with population comparisons matched on gender and birth year (n = 7787) through nationwide registries with annually updated information on marriage and cohabitation. Discrete-time survival models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the formation and termination of relationships, with adjustment for birth year, gender, and somatic and psychiatric comorbidities at entry. Individuals with NF1 were significantly less likely to form a relationship (HR = 0.65; 95% CI: 0.58-0.73), with the lowest association for individuals ≥33 years (HR 0.40; 95% CI: 0.25-0.63) and the highest for those aged 18-20 years (HR 0.82; 95% CI: 0.70-0.96). No significant difference was found for ending relationships (HR 1.00; 95% CI: 0.86-1.16). In conclusion, individuals who were hospitalized for NF1 are less likely to engage in marital or cohabiting relationships than population comparisons and are older when they form their first relationship. Once a relationship has been established, however, couples with a NF1-individual are not at greater risk of ending the relationship.

Neurofibromatosis type 1 (NF1) is a genetic condition characterized by numerous somatic manifestations. The psychosocial burden in adults has rarely been studied. We examined the prevalence of self-reported impairment of quality of life (QoL), symptoms of anxiety and depression and need for support, associated with disease severity and visibility. We conducted a nationwide cross-sectional study of all 467 adults with NF1 diagnosed between 1977 and 2016 at one of the two national centers for rare diseases in Denmark. A total of 244 (56% response rate) completed a questionnaire that included standard measures of QoL, symptoms of depression and anxiety, indicators of disease-related severity, visibility, and need for professional support. Associations between disease severity and visibility and psychosocial burden were analyzed in descriptive and multivariate models. We observed impaired QoL (mean = 81.3; 95% CI, 76.2; 86.4); 19% reported symptoms of depression (mean = 5.7; SD = 5.4), and 15% reported anxiety (mean = 5.1; SD = 5.2) at a clinical level. Adults with NF1 also reported requiring professional support for physical, psychological, and work-related problems. Disease severity and (partly) visibility were significantly (p < .0001) associated with psychosocial well-being and a requirement for support. This study provides new understanding of the factors associated with impaired QoL, indicating that follow-up care should be optimized into adult life., (© 2020 Wiley Periodicals, Inc.)

Purpose: The aim was to assess lifetime risk for hospitalization in individuals with neurofibromatosis 1 (NF1)., Methods: The 2467 individuals discharged with a diagnosis indicating NF1 or followed in a clinical center for NF1 were matched to 20,132 general population comparisons. Based on diagnoses in 12 main diagnostic groups and 146 subcategories, we calculated rate ratios (RRs), absolute excess risks (AERs), and hazard ratios for hospitalizations., Results: The RR for any first hospitalization among individuals with NF1 was 2.3 (95% confidence interval 2.2-2.5). A high AER was seen for all 12 main diagnostic groups, dominated by disorders of the nervous system (14.5% of all AERs), benign (13.6%) and malignant neoplasms (13.4%), and disorders of the digestive (10.5%) and respiratory systems (10.3%). Neoplasms, nerve and peripheral ganglia disease, pneumonia, epilepsy, bone and joint disorders, and intestinal infections were major contributors to the excess disease burden caused by NF1. Individuals with NF1 had more hospitalizations and spent more days in hospital than the comparisons. The increased risk for any hospitalization was observed for both children and adults, with or without an associated cancer., Conclusion: NF1 causes an overall greater likelihood of hospitalization, with frequent and longer hospitalizations involving all organ systems throughout life.

The introduction of pottery vessels to Europe has long been seen as closely linked with the spread of agriculture and pastoralism from the Near East. The adoption of pottery technology by hunter-gatherers in Northern and Eastern Europe does not fit this paradigm, and its role within these communities is so far unresolved. To investigate the motivations for hunter-gatherer pottery use, here, we present the systematic analysis of the contents of 528 early vessels from the Baltic Sea region, mostly dating to the late 6th-5th millennium cal BC, using molecular and isotopic characterization techniques. The results demonstrate clear sub-regional trends in the use of ceramics by hunter-gatherers; aquatic resources in the Eastern Baltic, non-ruminant animal fats in the Southeastern Baltic, and a more variable use, including ruminant animal products, in the Western Baltic, potentially including dairy. We found surprisingly little evidence for the use of ceramics for non-culinary activities, such as the production of resins. We attribute the emergence of these sub-regional cuisines to the diffusion of new culinary ideas afforded by the adoption of pottery, e.g. cooking and combining foods, but culturally contextualized and influenced by traditional practices., Competing Interests: We declare we have no competing interests., (© 2020 The Authors.)

We present the analysis of an osseous finger ring from a predominantly early Neolithic context in Denmark. To characterize the artefact and identify the raw material used for its manufacture, we performed micro-computed tomography scanning, zooarchaeology by mass spectrometry (ZooMS) peptide mass fingerprinting, as well as protein sequencing by liquid chromatography tandem mass spectrometry (LC-MS/MS). We conclude that the ring was made from long bone or antler due to the presence of osteons (Haversian canals). Subsequent ZooMS analysis of collagen I and II indicated that it was made from Alces alces or Cervus elaphus material. We then used LC-MS/MS analysis to refine our species identification, confirming that the ring was made from Cervus elaphus , and to examine the rest of the proteome. This study demonstrates the potential of ancient proteomics for species identification of prehistoric artefacts made from osseous material., Competing Interests: We declare we have no competing interests., (© 2020 The Authors.)

The rise of ancient genomics has revolutionised our understanding of human prehistory but this work depends on the availability of suitable samples. Here we present a complete ancient human genome and oral microbiome sequenced from a 5700 year-old piece of chewed birch pitch from Denmark. We sequence the human genome to an average depth of 2.3× and find that the individual who chewed the pitch was female and that she was genetically more closely related to western hunter-gatherers from mainland Europe than hunter-gatherers from central Scandinavia. We also find that she likely had dark skin, dark brown hair and blue eyes. In addition, we identify DNA fragments from several bacterial and viral taxa, including Epstein-Barr virus, as well as animal and plant DNA, which may have derived from a recent meal. The results highlight the potential of chewed birch pitch as a source of ancient DNA.

Most research on psychosocial consequences of neurofibromatosis type 1 (NF1) has focused on the relationship between disease factors and cognitive functioning. NF1 may impair domains of learning and attention, resulting in low academic performance. This study is the first nationwide population-based cohort study to investigate educational attainment and delay in completing mandatory school by persons with NF1. Educational information was collected from 550 persons at the age of 30 (born 1965-1984). They were diagnosed with NF1 in Denmark and compared to a cohort of NF1-free persons matched on gender and age (n = 4295). Multinomial logistic models were applied to estimate odds ratios (ORs) for obtaining short (≤9 years) or medium (10-12 years) education compared to long education (>12 years) by the age of 30 years. We calculated the probability of graduating 9 th year of mandatory school at different ages in 932 persons with NF1 and 7962 NF1-free persons (born 1965-2000) using quantile regression. The OR of educational completion for short- and medium-term education was three fold (95% CI 2.55-3.99) and 1.29 fold (95% CI 0.99-1.69) higher, respectively, for persons with NF1 than NF1-free persons after adjusting for birth year, gender, psychiatric and somatic morbidity and mother's education. Persons with NF1 were significantly delayed in graduating mandatory school education compared to NF1-free persons. When 90% of persons have graduated, persons with NF1 were 1.2 times older than the NF1-free persons. Experiencing delays in mandatory school likely affect further educational achievements and may impair employment and entering work force.

Huntington's disease is an inherited neuropsychiatric disorder characterized by a triad of symptoms: motor, cognitive and psychiatric. Psychiatric symptoms occur prior to the motor symptoms in approximately 50% of the cases, and knowledge of the psychiatric symptoms is essential in making an early diagnosis. In this article, we argue that further knowledge of the genetic background of Huntington's disease may contribute to a better understanding of the polygenetic psychiatric diseases such as schizophrenia and bipolar affective disorder.

The Danish Huntington's Disease Registry (DHR) is a nationwide family registry comprising 14 245 individuals from 445 Huntington's disease (HD) families of which the largest family includes 845 individuals in 8 generations. 1136 DNA and/or blood samples and 18 fibroblast cultures are stored in a local biobank. The birthplace of the oldest HD carrier in each of the 261 families of Danish origin was unevenly distributed across Denmark with a high number of families in the middle part of the peninsula Jutland and in Copenhagen, the capital. The prevalence of HD in Denmark was calculated to be 5-8:100 000. 1451 individuals in the DHR had the size of the HTT CAG repeat determined of which 975 had 36 CAG repeats or more (mean ± SD: 43,5 ± 4,8). Two unrelated individuals were compound heterozygous for alleles ≥36 CAGs, and 60 individuals from 34 independent families carried an intermediate allele., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Huntington's disease (HD) is an inherited neurodegenerative disorder characterised by movement disorder, cognitive symptoms and psychiatric symptoms with predominantly adult-onset. The mutant huntingtin protein leads to mitochondrial dysfunction in blood leukocytes. This discovery led to the investigation of the mitochondrial DNA (mtDNA) copy number relative to nuclear DNA (nDNA) in leukocytes from carriers of the HD mutation compared to healthy individuals. We found significantly reduced mtDNA/nDNA in HD mutation carriers compared to controls. A longitudinal study of archive DNA sample pairs from HD patients revealed a biphasic pattern of increasing mtDNA/nDNA before onset of motor symptoms and decreasing mtDNA/nDNA after., (Copyright © 2014 Elsevier B.V. and Mitochondria Research Society. All rights reserved.)

The Arctic is responding more rapidly to global warming than most other areas on our planet. Northward-flowing Atlantic Water is the major means of heat advection toward the Arctic and strongly affects the sea ice distribution. Records of its natural variability are critical for the understanding of feedback mechanisms and the future of the Arctic climate system, but continuous historical records reach back only ~150 years. Here, we present a multidecadal-scale record of ocean temperature variations during the past 2000 years, derived from marine sediments off Western Svalbard (79°N). We find that early-21st-century temperatures of Atlantic Water entering the Arctic Ocean are unprecedented over the past 2000 years and are presumably linked to the Arctic amplification of global warming.

Previous reports have highlighted a possible link between Huntington's disease (HD) and diabetes mellitus (DM), but the association has not been characterised in detail. A transgenic mouse model for HD, the R6/2 mouse, also develops diabetes. In the present study, we examined the R6/1 mouse, which carries a shorter CAG repeat than the R6/2 mouse, and found that, although not diabetic, the mice showed several signs of impaired glucose tolerance. First, following i.p. glucose injection, the blood glucose concentration was approximately 30% higher in young R6/1 mice (10 weeks) compared to wild-type mice (P = 0.004). In older mice (38 weeks), glucose tolerance was further impaired in both R6/1 and wild-type animals. Second, during glucose challenge, the R6/1 mice reached higher plasma insulin levels than wild-type mice, but the peripheral insulin sensitivity was normal as measured by injection of human or mouse insulin or when evaluated by the quantitative insulin sensitivity check index (QUICKI). Third, the beta cell volume was 17% and 39% smaller at 10 and 38 weeks of age, respectively, compared to age-matched wild-type littermates and the reduction was not caused by apoptosis at either age. Finally, we demonstrated the presence of the HD gene product, huntingtin (htt), in both alpha- and beta-cells in R6/1 islets of Langerhans. Since pancreatic beta cells and neurons share several common traits, clarification of the mechanism associating neurodegenerative diseases with diabetes might improve our understanding of the pathogenic events leading to both groups of diseases.

Purpose: We investigated the bone mineral status in patients with untreated Fabry disease (FD)., Methods: Descriptive, cross-sectional study in 53 patients with FD investigating bone mineral density (BMD)/content (dual energy x-ray absorptiometry scan), bone metabolism (parathyroid hormone, osteocalcin, and insulin-like growth factor I), and renal function (ethylene diamine tetraacetic acid clearance)., Results: Mean BMD z score at the lumbar spine and femoral neck were -0.05 +/- 1.46 SD and -0.37 +/- 1.02 SD, respectively. Approximately 50% had osteopenia in the hip or lumbar spine and additionally four had osteoporosis. Multivariate analysis including body weight, impaired renal function, and genotype overall explained 48% of the variance in lumbar spine BMD (P < 0.001), whereas body weight, impaired renal function, and menopausal status in the female population accounted for more than 50% of the variation in BMD of both the lumbar spine and femoral neck (both P < 0.001). Twenty percent of patients had hyperparathyroidism. Although the level of parathyroid hormone was significantly associated with impaired renal function, osteocalcin levels were significantly higher in patients with lumbar spine osteopenia or osteoporosis than in those with normal BMD., Conclusions: Osteopenia was present in approximately 50% of patients with untreated FD. Whether BMD and bone metabolism will improve after enzyme replacement therapy remains to be established.

Background: In order to maintain the most comprehensive structural annotation databases we must carry out regular updates for each proteome using the latest profile-profile fold recognition methods. The ability to carry out these updates on demand is necessary to keep pace with the regular updates of sequence and structure databases. Providing the highest quality structural models requires the most intensive profile-profile fold recognition methods running with the very latest available sequence databases and fold libraries. However, running these methods on such a regular basis for every sequenced proteome requires large amounts of processing power. In this paper we describe and benchmark the JYDE (Job Yield Distribution Environment) system, which is a meta-scheduler designed to work above cluster schedulers, such as Sun Grid Engine (SGE) or Condor. We demonstrate the ability of JYDE to distribute the load of genomic-scale fold recognition across multiple independent Grid domains. We use the most recent profile-profile version of our mGenTHREADER software in order to annotate the latest version of the Human proteome against the latest sequence and structure databases in as short a time as possible., Results: We show that our JYDE system is able to scale to large numbers of intensive fold recognition jobs running across several independent computer clusters. Using our JYDE system we have been able to annotate 99.9% of the protein sequences within the Human proteome in less than 24 hours, by harnessing over 500 CPUs from 3 independent Grid domains., Conclusion: This study clearly demonstrates the feasibility of carrying out on demand high quality structural annotations for the proteomes of major eukaryotic organisms. Specifically, we have shown that it is now possible to provide complete regular updates of profile-profile based fold recognition models for entire eukaryotic proteomes, through the use of Grid middleware such as JYDE.

We describe a patient with a combination of dystonic and parkinsonian signs. Paraclinical studies revealed a mutation in the GTP cyclohydrolase I gene (GCH1) and a decrease in [123I]-N-omega-fluoropropyl-2beta-carbomethoxy-3beta-(4-iodophenyl) nortropane (123I-FP-CIT) binding ratios indicative of Parkinson's disease. We conclude that the patient probably suffers from a variant of dopa-responsive dystonia (DRD) or two separate movement disorders, normally considered to be differential diagnoses, DRD and early-onset Parkinson's disease with resulting difficulties concerning treatment and prognosis., (Copyright (c) 2005 Movement Disorder Society.)

Hereditary spastic paraplegia (HSP) linked to the spastic gait gene 4 (SPG4) is controversial, as the "pure" form traditionally has been considered confined to the long axons of the spinal cord. However, recent immunolabeling experiments have demonstrated extensive Spastin expression in the cortex and striatum. This could indicate a more widespread neuropathology from mutations in the SPG4 gene than previously assumed. The aim of this study was therefore to ascertain the extent of cerebral involvement in SPG4 linked HSP by neuropsychological examination and measurement of the regional cerebral blood flow (rCBF) as an indirect marker of regional neuronal activity. Eighteen SPG4 patients and 18 matched control subjects were studied. Resting state rCBF was measured using Positron Emission Tomography (PET) and the (15)O-labelled water bolus technique and relative group differences were explored using Statistical Parametric Mapping (SPM 99). Neuropsychological assessment was performed using established and nationally validated tests (RH Basic Battery). Compared to healthy controls, the patient group had significantly decreased rCBF in the left fronto-temporal cortex (P<0.05), and more extensive changes were observed in a separate analysis of the most disabled individuals. The neuropsychological assessment revealed only significantly impaired recognition memory for faces. In summary, the findings support cerebral pathology in SPG4-linked HSP, although the decreased rCBF in fronto-temporal cortex was not associated with severe cognitive impairment.

We have previously reported a large Danish pedigree with autosomal dominant frontotemporal dementia (FTD) linked to chromosome 3 (FTD3). Here we identify a mutation in CHMP2B, encoding a component of the endosomal ESCRTIII complex, and show that it results in aberrant mRNA splicing in tissue samples from affected members of this family. We also describe an additional missense mutation in an unrelated individual with FTD. Aberration in the endosomal ESCRTIII complex may result in FTD and neurodegenerative disease.

Complex forms of hereditary spastic paraplegia (HSP) are rare and usually transmitted in an autosomal recessive pattern. A family of four generations with autosomal dominant hereditary spastic paraplegia (AD-HSP) and a complex phenotype with variably expressed co-existing ataxia, dysarthria, unipolar depression, epilepsy, migraine, and cognitive impairment was investigated. Genetic linkage analysis and sequencing of the SPG4 gene was performed and electrophysiologic investigations were carried out in six individuals and positron emission tomography (PET) in one patient. The disease was linked to the SPG4 locus on chromosome 2p as previously reported for pure HSP. Sequence analysis of the SPG4 (spastin) gene identified a novel 1593 C > T (GLN490Stop) mutation leading to premature termination of exon 12 with ensuing truncation of the encoded protein. However, the mutation was only identified in those individuals who were clinically affected by a complex phenotype consisting of HSP and cerebellar ataxia. Other features noted in this kindred including epilepsy, cognitive impairment, depression, and migraine did not segregate with the HSP phenotype or mutation, and therefore the significance of these features to SPG4 is unclear. Electrophysiologic investigation showed increased central conduction time at somatosensory evoked potentials measured from the lower limbs as the only abnormal finding in two affected individuals with the SPG4 mutation. Moreover, PET of one patient showed significantly relatively decreased regional cerebral blood flow in most of the cerebellum. We conclude that this kindred demonstrates a considerable overlap between cerebellar ataxia and spastic paraplegia, emphasizing the marked clinical heterogeneity of HSP associated with spastin mutations.

We report on a pair of monozygotic twins belonging to a family segregating Huntington disease (HD). In routine DNA analysis of blood cells, they displayed three alleles of the CAG repeat sequence in the HD gene. Two different cell lines, carrying the normal allele together with either an expanded allele with 47 CAGs or an intermediate allele with 37 CAGs, were detected in blood and buccal epithelium from both twins. To our knowledge, this is the first case described of HD gene CAG repeat length mosaicism in blood cells. Haplotype analysis established that the 37 CAG allele most likely arose by contraction of the maternal 47 CAG allele. The contraction must have taken place postzygotically, possibly at a very early stage of development, and probably before separation of the twins. One of the twins has presented symptoms of HD for 4 years; his skin fibroblasts and hair roots carried only the cell line with the 47 CAG repeat allele. The other twin, who is without symptoms at present, displayed mosaicism in skin fibroblasts and hair roots. If the proportion of the two cell lines in the brain of each twin resembles that of their hair roots (another tissue originating from the ectoderm), the mosaicism in the unaffected twin would mean that only a part of his brain cells carried the expanded allele, which could explain why he, in contrast to his brother, has no symptoms at this time.

Currently, the Genomic Threading Database (GTD) contains structural assignments for the proteins encoded within the genomes of nine eukaryotes and 101 prokaryotes. Structural annotations are carried out using a modified version of GenTHREADER, a reliable fold recognition method. The Gen THREADER annotation jobs are distributed across multiple clusters of processors using grid technology and the predictions are deposited in a relational database accessible via a web interface at http://bioinf.cs.ucl.ac.uk/GTD. Using this system, up to 84% of proteins encoded within a genome can be confidently assigned to known folds with 72% of the residues aligned. On average in the GTD, 64% of proteins encoded within a genome are confidently assigned to known folds and 58% of the residues are aligned to structures.

Unlabelled: The Genomic Threading Database currently contains structural annotations for the genomes of over 100 recently sequenced organisms. Annotations are carried out by using our modified GenTHREADER software and through implementing grid technology., Availability: http://bioinf.cs.ucl.ac.uk/GTD

Background: Huntington's disease (HD) is an inherited neurodegenerative disorder which is caused by an expansion of a CAG repeat sequence in the HD gene. The repeat encodes an expanded polyglutamine tract in the protein huntingtin. The still unknown pathological mechanisms leading to death of specific neurons in the brains of HD patients correlate with the expression of mutant huntingtin. Therefore, we have studied whether mutant huntingtin expression can be downregulated by antisense technique., Methods: NT2 precursor cells and differentiated postmitotic NT2-N neurons, respectively, were transfected with plasmid constructs containing exon 1 of the HD gene with expanded CAG repeats in frame with the reporter protein EGFP. The transfected cell cultures were treated with a phosphorothioated antisense oligonucleotide (PS-ASHD/20+) or a control oligonucleotide either by cotransfection or by addition to the culture medium., Results: Expression of the fusion protein containing the mutant huntingtin fragment resulted in diffuse green fluorescence in the cytoplasm and formation of aggregates in some of the NT2 cells and NT2-N neurons. We obtained antisense sequence-specific inhibition of expression of the fusion protein and/or suppression of the aggregate formation in both cell types. In the NT2 cells the antisense effect was dependent on the way of administration of the oligo., Conclusions: The PS-antisense oligo is effective in downregulation of mutant huntingtin, and the reduction of aggregate formation is a sensitive biological marker. The findings suggest that antisense knockdown of huntingtin could be a useful strategy for treatment of HD, and could also be suitable for studies of the normal and pathological function of huntingtin in different cellular model systems., (Copyright 2003 John Wiley & Sons, Ltd.)

Two families were referred with different clinical diagnoses of dystonia. Twenty-four family members were examined clinically, and mutation analyses were performed. Most of the affected individuals had laryngeal myoclonus and more severe dystonia of the legs than usually reported in myoclonus-dystonia syndrome. Sequence analyses revealed a previously unreported deletion (974delC or R325X) in exon 7 in the epsilon-sarcoglycan gene in members of both families. The two families were found to be related.

Transgenic mice expressing exon 1 of the human Huntington's disease (HD) gene carrying a 115 CAG repeat (line R6/1) are characterized by a neurologic phenotype involving molecular, behavioral and motor disturbances. We have characterized the R6/1 to establish a set of biomarkers, which could be semi-quantitatively compared. We have measured motor fore- and hindlimb coordination, fore- and hindpaw footprinting, general activity and anxiety, feetclasping, developmental instability. Molecular investigations involved measurements of cannabinoid receptor 1 mRNA, met-enkephalin peptide, dopamine and cyclic AMP-regulated phosphoroprotein 32 kDa and neuronal inclusions. Molecular and behavioral testing was performed on female hemizygotic R6/1 transgenic mice and female wildtype littermates between 6 and 36 weeks of age. We show that the cannabinoid receptor 1 receptor is severely and rapidly downregulated in the R6/1 mouse between the 8(th) to the 10(th) week of age. At 14 weeks of age the first transgenic mice showed a behavioral phenotype measured by feetclasping. However, there was great variation between the individual animals. At 11 weeks of age the mice demonstrated progressively increasing developmental instability as measured by fluctuating asymmetry. Weight differences were evident by 22 weeks of age. Mice tested at 23 and 24 weeks of age showed significant impairments in open field and plus-maze analysis respectively. We observed no significant abnormalities in stride length of the R6/1 mouse model. As the analyzed parameters are easily detected and measured, the R6/1 mouse appears to be a good model for evaluating new drugs or types of therapy for HD.

Ion channels formed by expanded polyglutamine tracts have been proposed to play an important role in the pathological processes leading to neurodegeneration in Huntington's disease and other CAG repeat diseases. We tested the capacity of a huntingtin fragment containing an expanded polyglutamine tract to form ion channels in two cell types. Whole cell current from Xenopus oocytes was recorded using two-electrode voltage-clamp technique, and whole cell current from CHO-K1 cells was recorded by patch-clamp technique. The fragment with an expanded polyglutamine sequence induced no change in the currents recorded in any of the two expression systems, indicating no changes in ion channel activity. The results therefore argue against the proposed hypothesis of expanded polyglutamines forming ion channels., (Copyright 2002 Wiley-Liss, Inc.)

A study of Danish probands with primary torsion dystonia is presented. The probands were examined clinically and biochemically to exclude secondary dystonia. Mutation analyses for the GAG-deletion in the DYT1 gene were performed on 107 probands; and the mutation was detected in three. All three probands had the classical phenotype of DYT1-dystonia, but only one had a family history of dystonia. The other two probands had, obviously, sporadic DYT1-dystonia, one of which was caused by a de novo mutation, while the other one had a parent being an asymptomatic carrier. De novo mutations in the DYT1 gene are seldom reported although independent founder mutations are known to have occurred. The frequency of DYT1-dystonia was low in our study even though several probands had early onset generalised dystonia. None of the probands in our study with other types of dystonia had the GAG-deletion as reported in other studies. The difficulties in genetic counselling concerning the heterogeneity of dystonia exemplified by DYT1-dystonia are outlined.

There are at least seven clinically indistinguishable but genetically different types of autosomal dominant pure spastic paraplegia (ADPSP). In this study we investigated electrophysiological characteristics in patients with ADPSP linked to chromosome 2p (SPG4). Twelve patients from six different families with ADPSP linked to chromosome 2p and 15 control persons were included. Electromyography (EMG), motor and sensory nerve conduction, and motor evoked potentials using single and paired transcranial magnetic stimulation (PTMS) was performed. From the peripheral nervous system we found signs of motor and sensory axonal neuropathy. Motor evoked potentials disclosed greatly reduced corticospinal tract conduction velocity and amplitude of evoked potentials to the lower extremities indicating that the very marked spasticity predominantly seems to rely on dysfunction of the fast conducting axons of the pyramidal tract. PTMS showed an increased intracortical facilitation (ICF), which may reflect an impaired function of gamma-aminobutyric acid (GABA)-controlled interneuronal circuits in the motor cortex, alternatively an increased glutamatergic transmission or a compensatory recruitment of a larger number of neurones with corticospinal projections.

Objectives: Increasing evidence suggests that metabolic changes predate neuronal death in Huntington's disease and emission tomography methods (PET and SPECT) have shown changes in glucose consumption and receptor function in early and possibly even presymptomatic disease. Because the GABA(A)-benzodiazepine receptor complex (BZR) is expressed on virtually all cerebral neurons BZR density images may be used to detect neuronal death. In this study the regional cerebral [(123)I]iomazenil binding to BZR was determined in patients with Huntington's disease and normal controls by a steady state method and SPECT., Methods: Seven patients mildly to moderately affected by Huntington's disease and seven age matched controls were studied. Brain CT was performed on all subjects. In each subject two [(123)I]iomazenil-SPECT measurements were acquired-one with and one without infusion of flumazenil. The affinity constant of flumazenil (Kd) was calculated from the paired distribution volumes (DV) and the free plasma flumazenil concentration. The distribution volume of [(123)I]iomazenil in the unblocked condition (DV(0)) reflects the ratio between BZR density and Kd., Results: Flumazenil Kd was similar in the Huntington's disease group and the control group (11.3 v 11.2 mM). For the Huntington's disease group a 31% reduction in striatal DV(0) (p=0.03) was found. In the cortical regions, DV(0) was similar in patients and in controls. In Huntington's disease, DV(0) correlated significantly with functional capacity (p=0.04) and chorea symptoms (p=0.02). The clinically least affected patients displayed DV(0)s within the range of those of the control group (19-35 ml/ml)., Conclusions: The finding of an unchanged Kd of flumazenil in patients indicates that the BZR is functionally intact in Huntington's disease. That is, the reduction in DV(0) for BZR represents a selective decrease in the number of striatal BZRs. DV(0) significantly correlated with functional loss and [(123)I]iomazenil-SPECT could be an important tool for validation of the effect of future therapeutic strategies aimed at limiting oxidative stress and free radicals in Huntington's disease.

Objective: The purpose of the present study was to relate the number of platelet serotonin transporters in unipolar and bipolar patients and in control subjects to two polymorphisms in the serotonin transporter gene: a VNTR in intron 2 and a deletion/insertion in the promoter region., Method: Density of platelet serotonin transporters was determined by radioligand binding analysis. Genotyping was performed by PCR amplification of polymorphic regions followed by size determination of the obtained fragments., Results: The control subjects and the two groups of patients were similar with respect to the genotype and allele distribution belonging to the two polymorphisms in the serotonin transporter gene for. An interaction between status (control, unipolar- or bipolar patient) and VNTR genotype regarding the number of platelet serotonin transporters was observed; unipolar patients with the genotype 12/10 had more platelet serotonin transporters than bipolar patients and controls with this genotype. No association related to the polymorphism was found in the promoter region of the serotonin transporter gene., Conclusion: An association was observed between the polymorphism in intron 2 of the serotonin transporter gene and the number of platelet serotonin transporters. Unipolar patients with a particular genotype had more platelet serotonin transporters than the corresponding controls and bipolar patients.

The Huntington disease gone encodes the protein huntington, which is widely expressed during embryonic development and in mature tissues. In order to elucidate the physiological function of huntington, which so far is unknown, we intend to study the effect of antisense down-regulated huntington expression. We have found an inhibiting effect of a phosphorothioated oligodeoxynucleotide (PS-ODN) added to the culture medium of embryonic teratocarcinoma cells (NT2) and postmitotic neurons (NT2N neurons) differentiated from the NT2 cells. Specific inhibition of expression of endogenous huntington was achieved in NT2N neurons in the concentration range of 1-5 microM PS-ODN, whereas no inhibition was obtained in NT2 cells. We describe in detail the selection of the target sequence for the antisense oligo and the uptake, intracellular distribution, and stability of the antisense PS-ODN in the two cell types. Antisense down-regulation of huntington in this model of human neurons represents a suitable approach to study its normal function.

Dystonia is a heterogeneous, neurological disease characterized by involuntary, sustained muscle contractions, frequently causing twisting and repetitive movements or abnormal postures. The patients are often difficult to diagnose, and the treatment is almost always only symptomatic. It is believed that about 75% of all patients with dystonia have primary dystonia, and 25-85% of these are hereditary. Seven gene loci for autosomal, dominant inherited dystonia and two for X-linked, recessive inherited dystonia are known at present, but the underlying genes are known only for DYT1 and DYT5. Testing is possible for these two in Denmark. Growing molecular genetic knowledge will lead to earlier and correct diagnosing, including prognosis, and may elucidate the pathogenesis, making better treatment possible.