7 research outputs found
Rare nonsynonymous variants in SORT1 are associated with increased risk for frontotemporal dementia
We investigated the genetic role of sortilin (SORT1) in frontotemporal dementia (FTD). SORT1 is the neuronal receptor for granulin, encoded by the progranulin gene (GRN), a major causal gene for inherited FTD. In Belgian cohorts of 636 FTD patients and 1066 unaffected control individuals, we identified 5 patient-only nonsynonymous rare variants in SORT1. Rare variant burden analysis showed a significant increase in rare coding variants in patients compared to control individuals (p = 0.04), particularly in the β-propeller domain (p = 0.04), with 2 rare variants located in the predicted binding site for GRN (p = 0.001). We extended these observations by analyzing 3 independent patient/control cohorts sampled in Spain, Italy, and Portugal by partners of the European Early-Onset Dementia Consortium, together with 1155 FTD patients and 1161 control persons. An additional 7 patient-only nonsynonymous variants were observed in SORT1 in European patients. Meta-analysis of the rare nonsynonymous variants in the Belgian and European patient/control cohorts revealed a significant enrichment in FTD patients (p = 0.006), establishing SORT1 as a genetic risk factor for FTD
A pan-European study of the C9orf72 repeat associated with FTLD: geographic prevalence, genomic instability, and intermediate repeats.
Rare nonsynonymous variants in SORT1 are associated with increased risk for frontotemporal dementia
We investigated the genetic role of sortilin (SORT1) in frontotemporal dementia (FTD). SORT1 is the neuronal receptor for granulin, encoded by the progranulin gene (GRN), a major causal gene for inherited FTD. In Belgian cohorts of 636 FTD patients and 1066 unaffected control individuals, we identified 5 patient-only nonsynonymous rare variants in SORT1. Rare variant burden analysis showed a significant increase in rare coding variants in patients compared to control individuals (p = 0.04), particularly in the β-propeller domain (p = 0.04), with 2 rare variants located in the predicted binding site for GRN (p = 0.001). We extended these observations by analyzing 3 independent patient/control cohorts sampled in Spain, Italy, and Portugal by partners of the European Early-Onset Dementia Consortium, together with 1155 FTD patients and 1161 control persons. An additional 7 patient-only nonsynonymous variants were observed in SORT1 in European patients. Meta-analysis of the rare nonsynonymous variants in the Belgian and European patient/control cohorts revealed a significant enrichment in FTD patients (p = 0.006), establishing SORT1 as a genetic risk factor for FTD
A pan-european study of the C9orf72 repeat associated with FTLD: geographic prevalence, genomic instability and intermediate repeats.
We assessed the geographical distribution of C9orf72 G4C2 expansions in a pan-European frontotemporal lobar degeneration (FTLD) cohort (n = 1205), ascertained by the European Early-Onset Dementia (EOD) consortium. Next, we performed a meta-analysis of our data and that of other European studies, together 2,668 patients from 15 Western European countries. The frequency of the C9orf72 expansions in Western Europe was 9.98% in overall FTLD, with 18.52% in familial, and 6.26% in sporadic FTLD patients. Outliers were Finland and Sweden with overall frequencies of respectively 29.33% and 20.73%, but also Spain with 25.49%. In contrast, prevalence in Germany was limited to 4.82%. In addition, we studied the role of intermediate repeats (7 to 24 repeat units), which are strongly correlated with the risk haplotype, on disease and C9orf72 expression. In vitro reporter gene expression studies demonstrated significantly decreased transcriptional activity of C9orf72 with increasing number of normal repeat units, indicating that intermediate repeats might act as predisposing alleles and in favor of the loss-of-function disease mechanism. Further, we observed a significantly increased frequency of short indels in the GC-rich low complexity sequence (LCS) adjacent to the G4C2 repeat in C9orf72 expansion carriers (p < 0.001) with the most common indel creating one long contiguous imperfect G4C2 repeat which is likely more prone to replication slippage and pathological expansion
A Pan-European study of the C9orf72 Repeat Associated with FTLD: Geographic Prevalence, Genomic Instability and Intermediate Repeats.
An experimental test to compare potential and realised specificity in ticks with different ecologies
Recommended from our members
Mendelian and sporadic FTD: disease risk and avenues from genetics to disease pathways through in silico modelling.
Frontotemporal dementia (FTD) is regarded as the second most common form of young-onset dementia after Alzheimer's disease (AD).FTD is a complex neurodegenerative condition characterised by heterogeneous clinical, pathological and genetic features. No efficient measures for early diagnosis and therapy are available.Familial (Mendelian) forms of disease have been studied over the past 20 years. Conversely, the genetics of sporadic forms of FTD (up to 70% of all cases) is understudied and still poorly understood. All this taken together suggests that more powerful and in-depth studies to tackle missing heritability and define the genetic architecture of sporadic FTD, with particular focus on the different subtypes (i.e. clinical and pathological diagnoses), are warranted.In parallel, it will be critical to translate the genetic findings into functional understanding of disease, i.e. moving from the identification of risk genes to the definition of risk pathways. It will be necessary to implement a paradigm shift - from reductionist to holistic approaches - to better interpret genetics and assist functional studies aimed at modelling and validating such risk pathways.In this chapter, we focus on the heterogeneous features of FTD touching upon its complex genetic landscape and discuss how novel approaches (e.g. computationally driven systems biology) promise to revolutionise the translation of genetic information into functional understanding of disease pathogenesis