Search

Objectives The main objective of the present study is to study the therapeutic efficiency of doxycycline in a double-blinded randomised phase II study in a cohort of patients with sporadic Creutzfeldt-Jakob disease (sCJD). Methods From the National Reference Center of TSE Surveillance in Germany, patients with probable or definite sCJD were recruited for a double-blinded randomised study with oral doxycycline (EudraCT 2006-003934-14). In addition, we analysed the data from patients with CJD who received compassionate treatment with doxycycline in a separate group. Potential factors which influence survival such as age at onset, gender, codon 129 polymorphism and cognitive functions were evaluated. The primary outcome measure was survival. Results Group 1: in the double-blinded randomised phase II study, 7 patients in the treatment group were compared with 5 controls. Group 2: 55 patients with sCJD treated with oral doxycycline were analysed and compared with 33 controls by a stratified propensity score applied to a Cox proportional hazard analysis. The results of both studies were combined by means of a random-effects meta-analysis. A slight increase in survival time in the doxycycline treatment group was observed (p=0.049, HR=0.63 (95% CI 0.402 to 0.999)). Conclusions On the basis of our studies, a larger trial of doxycycline should be performed in persons in the earliest stages of CJD. Trial registration number EudraCT 2006-003934-14; Results.

To describe the clinical syndrome and diagnostic tests in patients with genetic prion diseases (gPD) in Germany. Clinical features, MRI, EEG, and CSF markers were studied in 91 patients (28 D178N, 20 E200K, 17 inserts, 13 V210I, 8 P102L, 5 E196K). Dementia (35 %) and ataxia (29 %) were the most common initial symptoms and signs. A wide variety and high frequency of neurological/psychiatric symptoms and signs was found during disease course in all patients independently of the type of the mutation. Psychiatric manifestations were frequent (87 %). Neuropsychological abnormalities were observed in 67 %, and aphasia was the most common disturbance (45 %). In E200K, V210I and D178N patients, visual/oculomotor deficits were followed by ataxia early in the disease. Dementia followed by ataxia at onset was common in patients with insert and E196K mutation. P102L patients had isolated ataxia over a longer time period followed by pyramidal signs. Dementia was present only late in the disease course. All clinical routine tests such as MRI, EEG and CSF tests were less sensitive than in sporadic CJD. We provide the first detailed analysis of clinical signs and symptoms in a large group of patients with gPD. Frequency of clinical symptoms and signs was similar in different mutations in a later disease course, but the sequence of occurrence may be of great diagnostic importance. CSF markers were shown to be more sensitive than MRI and EEG.

International audience; We report the presence of infectivity in erythrocytes, leukocytes, and plasma of 1 person with variant Creutzfeldt-Jakob disease and in the plasma of 2 in 4 persons whose tests were positive for sporadic Creutzfeldt-Jakob disease. The measured infectivity levels were comparable to those reported in various animals with transmissible spongiform encephalopathies.

More than 100,000 genetic variants are reported to cause Mendelian disease in humans, but the penetrance-the probability that a carrier of the purported disease-causing genotype will indeed develop the disease-is generally unknown. We assess the impact of variants in the prion protein gene (PRNP) on the risk of prion disease by analyzing 16,025 prion disease cases, 60,706 population control exomes, and 531,575 individuals genotyped by 23andMe Inc. We show that missense variants in PRNP previously reported to be pathogenic are at least 30 times more common in the population than expected on the basis of genetic prion disease prevalence. Although some of this excess can be attributed to benign variants falsely assigned as pathogenic, other variants have genuine effects on disease susceptibility but confer lifetime risks ranging from < 0.1 to similar to 100%. We also show that truncating variants in PRNP have position-dependent effects, with true loss-of-function alleles found in healthy older individuals, a finding that supports the safety of therapeutic suppression of prion protein expression.

We performed a genome-wide association (GWA) study in 434 sporadic Creutzfeldt-Jakob disease (sCJD) patients and 1939 controls from the United Kingdom, Germany and The Netherlands. The findings were replicated in an independent sample of 1109 sCJD and 2264 controls provided by a multinational consortium. From the initial GWA analysis we selected 23 SNPs for further genotyping in 1109 sCJD cases from seven different countries. Five SNPs were significantly associated with sCJD after correction for multiple testing. Subsequently these five SNPs were genotyped in 2264 controls. The pooled analysis, including 1543 sCJD cases and 4203 controls, yielded two genome wide significant results: rs6107516 (p-value=7.62x10-9) a variant tagging the prion protein gene (PRNP); and rs6951643 (p-value=1.66x10-8) tagging the Glutamate Receptor Metabotropic 8 gene (GRM8). Next we analysed the data stratifying by country of origin combining samples from the pooled analysis with genotypes from the 1000 Genomes Project and imputed genotypes from the Rotterdam Study (Total n=12967). The meta-analysis of the results showed that rs6107516 (p-value=3.00x10-8) and rs6951643 (p-value=3.91x10-5) remained as the two most significantly associated SNPs. Rs6951643 is located in an intronic region of GRM8, a gene that was additionally tagged by a cluster of 12 SNPs within our top100 ranked results. GRM8 encodes for mGluR8, a protein which belongs to the metabotropic glutamate receptor family, recently shown to be involved in the transduction of cellular signals triggered by the prion protein. Pathway enrichment analyses performed with both Ingenuity Pathway Analysis and ALIGATOR postulates glutamate receptor signalling as one of the main pathways associated with sCJD. In summary, we have detected GRM8 as a novel, non-PRNP, genome-wide significant marker associated with heightened disease risk, providing additional evidence supporting a role of glutamate receptors in sCJD pathogenesis. This study was supported by: UK: the National CJD Research and Surveillance UK Unit is funded by the Department of Health and the Scottish Government Health Department. The National CJD Research and Surveillance Unit is funded by the Policy Research Programme in the Department of Health. Germany: This work was supported by a grant from the European Commission (Protecting the food chain from prions: shaping European priorities through basic and applied research (PRIORITY, N° 222887) Project number: FP7-KBBE-2007-2A). The study was performed within the recently established Clinical Dementia Center at the University Medical Center Göttingen and was partly supported by grants from the EU Joint Programme – Neurodegenerative Disease Research (JPND - DEMTEST "Biomarker based diagnosis of rapid progressive dementias optimization of diagnostic protocols", 01ED1201A). This study was funded by the Robert Koch Institute through funds from the Federal Ministry of Health (grant no. 1369-341). Italy: The Italian Registry of CJD and related disorders is funded by the Ministry of Health, National Centre for Disease Prevention and Control, Central Actions.This work was partly supported by grant from the EU Joint Programme – Neurodegenerative Disease Research (JPND-DEMTEST “Biomarker based diagnosis of rapid progressive dementias-optimization of diagnostic protocols”, 01ED1201A). The Netherlands: the generation and management of genome-wide association study (GWAS) genotype data for the Rotterdam Study is supported by the Netherlands Organization of Scientific Research NWO Investments (nr. 175.010.2005.011, 911-03-012). This study is funded by the Research Institute for Diseases in the Elderly (014-93-015; RIDE2), the Netherlands Genomics Initiative (NGI)/Netherlands Organisation for Scientific Research (NWO) project nr. 050-060-810. The Rotterdam Study is funded by Erasmus Medical Center and Erasmus University, Rotterdam, Netherlands Organization for the Health Research and Development (ZonMw), the Research Institute for Diseases in the Elderly (RIDE), the Ministry of Education, Culture and Science, the Ministry for Health, Welfare and Sports, the European Commission (DG XII), and the Municipality of Rotterdam. YSA is supported by Russian Science Foundation (RSCF) grant 14-14-00313. Spain. PSJ was supported by a grant from FIS (PI12/02288) and JPND project DEMTEST (PI11/03028). AC is supported by PI13/01136 Acción Estratégica de Salud del Instituto de Salud Carlos III e INNOPHARMA. Australia: The Australian National Creutzfeldt-Jakob Disease Registry (ANCJDR) is funded by the Commonwealth Department of Health. SJC is supported by a NHMRC Practitioner Fellowship (#APP1005816). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript Sí

The molecular subtype of sporadic Creutzfeldt-Jakob disease (sCJD) is an important prognostic marker for patient survival. However, subtype determination is not possible during lifetime. Because the rate of disease progression is associated with the molecular subtype, this study aimed at investigating if total tau, a marker of neuronal death, allows premortem diagnosis of molecular subtype when codon 129 genotype is known. Two hundred ninety-six sCJD patients were tested for their cerebrospinal fluid total tau level at the time of diagnosis and were investigated for their sCJD subtype postmortem. There was a significant association between tau levels and the prion protein type in patients with codon 129 MM (p < 0.001), MV (p = 0.004), and VV (p = 0.001) genotype. Receiver operating characteristic analyses showed values of area under the curve of 0.76-0.80 for the different genotypes indicating a good diagnostic validity of the test. Total tau can be used as a diagnostic test for the assessment of prion protein type when codon 129 genotype is known. It provides valuable information for physicians and next of kin about the further course of disease.

BACKGROUND: In absence of a positive family history, the diagnosis of fatal familial insomnia (FFI) might be difficult because of atypical clinical features and low sensitivity of diagnostic tests. FFI patients usually do not fulfil the established classification criteria for Creutzfeldt-Jakob disease (CJD); therefore, a prion disease is not always suspected. OBJECTIVE: To propose an update of diagnostic pathway for the identification of patients for the analysis of D178-M129 mutation. DESIGN AND METHODS: Data on 41 German FFI patients were analysed. Clinical symptoms and signs, MRI, PET, SPECT, polysomnography, EEG and cerebrospinal fluid biomarkers were studied. RESULTS: An algorithm was developed which correctly identified at least 81% of patients with the FFI diagnosis during early disease stages. It is based on the detection of organic sleep disturbances, either verified clinically or by a polysomnography, and a combination of vegetative and focal neurological signs and symptoms. Specificity of the approach was tested on three cohorts of patients (MM1 sporadic CJD patients, non-selected sporadic CJD and other neurodegenerative diseases). CONCLUSIONS: The proposed scheme may help to improve the clinical diagnosis of FFI. As the sensitivity of all diagnostic tests investigated but polysomnography is low in FFI, detailed clinical investigation is of special importance. peerReviewed

Background/Aims: Since detection of the prion protein gene (PRNP) more than 30 mutations have been discovered. Some have only been found in single case reports without known intrafamilial accumulation or neuropathological proof so that the causal connection between mutation and disease could not be proved. Those patients often present atypical clinical phenotypes, and it is not unusual that they are classified as diseases other than Creutzfeldt-Jakob disease (CJD). Methods: Cases of suspected CJD have been reported to the national reference center for prion diseases. Clinical and diagnostic data were collected, and a classification of definite, possible or probable prion disease was made. Molecular analysis of PRNP was performed by capillary sequencing. Results: We have described 4 cases with atypical clinical and diagnostic findings and unknown mutations in PRNP so far. Conclusion: Three patients fulfilled the criteria of probable CJD, and 1 patient fulfilled the criteria of possible CJD but the clinical picture in none of the patients was typical CJD; hence, it remained questionable whether the mutations were causal of the disease.

Prion diseases are a diverse group of neurodegenerative conditions, caused by the templated misfolding of prion protein. Aside from the strong genetic risk conferred by multiple variants of the prion protein gene (PRNP), several other variants have been suggested to confer risk in the most common type, sporadic Creutzfeldt-Jakob disease (sCJD) or in the acquired prion diseases. Large and rare copy number variants (CNVs) are known to confer risk in several related disorders including Alzheimer's disease (at APP), schizophrenia, epilepsy, mental retardation, and autism. Here, we report the first genome-wide analysis for CNV-associated risk using data derived from a recent international collaborative association study in sCJD (n = 1147 after quality control) and publicly available controls (n = 5427). We also investigated UK patients with variant Creutzfeldt-Jakob disease (n = 114) and elderly women from the Eastern Highlands of Papua New Guinea who proved highly resistant to the epidemic prion disease kuru, who were compared with healthy young Fore population controls (n = 395). There were no statistically significant alterations in the burden of CNVs >100, >500, or >1000 kb, duplications, or deletions in any disease group or geographic region. After correction for multiple testing, no statistically significant associations were found. A UK blood service control sample showed a duplication CNV that overlapped PRNP, but these were not found in prion disease. Heterozygous deletions of a 3′ region of the PARK2 gene were found in 3 sCJD patients and no controls (p = 0.001, uncorrected). A cell-based prion infection assay did not provide supportive evidence for a role for PARK2 in prion disease susceptibility. These data are consistent with a modest impact of CNVs on risk of late-onset neurologic conditions and suggest that, unlike APP, PRNP duplication is not a causal high-risk mutation.

© 2014 by The American Society of Human Genetics. All rights reserved. Anticipation is the phenomenon whereby age of onset in genetic disease decreases in successive generations. Three independent reports have claimed anticipation in Creutzfeldt-Jakob disease (CJD) caused by the c.598G>A mutation in PRNP encoding a p.Glu200Lys (E200K) substitution in the prion protein. If confirmed, this finding would carry clear implications for genetic counseling. We analyzed pedigrees with this mutation from four prion centers worldwide (n = 217 individuals with the mutation) to analyze age of onset and death in affected and censored individuals. We show through simulation that selective ascertainment of individuals whose onset falls within the historical window since the mutation's 1989 discovery is sufficient to create robust false signals both of anticipation and of heritability of age of onset. In our data set, the number of years of anticipation observed depends upon how strictly the data are limited by the ascertainment window. Among individuals whose disease was directly observed at a study center, a 28-year difference between parent and child age of onset is observed (p = 0.002), but including individuals ascertained retrospectively through family history reduces this figure to 7 years (p = 0.005). Applying survival analysis to the most thoroughly ascertained subset of data eliminates the signal of anticipation. Moreover, even non-CJD deaths exhibit 16 years anticipation (p = 0.002), indicating that ascertainment bias can entirely explain observed anticipation. We suggest that reports of anticipation in genetic prion disease are driven entirely by ascertainment bias. Guidelines for future studies claiming statistical evidence for anticipation are suggested.