			Home About us Contact

Progranulin Gene (progranulin + gene)

Distribution by Scientific Domains

Medical Sciences	50%
Life Sciences	50%

Selected Abstracts

Characteristics of frontotemporal dementia patients with a Progranulin mutation

ANNALS OF NEUROLOGY, Issue 3 2006
Edward D. Huey MD
Objective Mutations in the Progranulin gene (PGRN) recently have been discovered to be associated with frontotemporal dementia (FTD) linked to 17q21 without identified MAPT mutations. The range of mutations of PGRN that can result in the FTD phenotype and the clinical presentation of patients with PGRN mutations have yet to be determined. Methods In this study, we examined 84 FTD patients from families not known previously to have illness linked to chromosome 17 for identified PGRN and MAPT mutations and sequenced the coding exons and the flanking intronic regions of PGRN. We compared the prevalence, clinical characteristics, magnetic resonance imaging and 18-fluoro-deoxyglucose positron emission tomography results, and neuropsychological testing of patients with the PGRN R493X mutation with those patients without identified PGRN mutations. Results We discovered a new PGRN mutation (R493X) resulting in a stop codon in two patients. This was the only PGRN mutation identified in our sample. The patients with the PGRN R493X mutation had a rapid illness course and had predominant right-sided atrophy and hypometabolism on magnetic resonance imaging and 18-fluoro-deoxyglucose positron emission tomography. The affected father of one of the patients with the PGRN R493X mutation showed frontal and temporal atrophy without neurofibrillary tangles on neuropathological examination. Interpretation Known PGRN and MAPT mutations were rare and of similar prevalence in our sample (2 compared with 1/84). The patients with the PGRN R493X mutation had a clinical presentation comparable with other behavior-predominant FTD patients. The neuropathology of an affected family member of a patient with the PGRN R493X mutation appears not to be Alzheimer's disease. Ann Neurol 2006;60:374,380 This article includes supplementary materials available via the Internet at http://www.interscience.wiley.com/jpages/0364-5134/suppmat [source]

Molecular characterization of novel progranulin (GRN) mutations in frontotemporal dementia,

HUMAN MUTATION, Issue 4 2008
Odity Mukherjee
Abstract Frontotemporal dementia (FTD) is a clinical term encompassing dementia characterized by the presence of two major phenotypes: 1) behavioral and personality disorder, and 2) language disorder, which includes primary progressive aphasia and semantic dementia. Recently, the gene for familial frontotemporal lobar degeneration (FTLD) with ubiquitin-positive, tau-negative inclusions (FTLD-U) linked to chromosome 17 was cloned. In the present study, 62 unrelated patients from the Washington University Alzheimer's Disease Research Center and the Midwest Consortium for FTD with clinically diagnosed FTD and/or neuropathologically characterized cases of FTLD-U with or without motor neuron disease (MND) were screened for mutations in the progranulin gene (GRN; also PGRN). We discovered two pathogenic mutations in four families: 1) a single-base substitution within the 3, splice acceptor site of intron 6/exon 7 (g.5913A>G [IVS6,2A>G]) causing skipping of exon 7 and premature termination of the coding sequence (PTC); and 2) a missense mutation in exon 1 (g.4068C>A) introducing a charged amino acid in the hydrophobic core of the signal peptide at residue 9 (p.A9D). Functional analysis in mutation carriers for the splice acceptor site mutation revealed a 50% decrease in GRN mRNA and protein levels, supporting haploinsufficiency. In contrast, there was no significant difference in the total GRN mRNA between cases and controls carrying the p.A9D mutation. Further, subcellular fractionation and confocal microscopy indicate that although the mutant protein is expressed, it is not secreted, and appears to be trapped within an intracellular compartment, possibly resulting in a functional haploinsufficiency. Hum Mutat 29(4), 512,521, 2008. © 2008 Wiley-Liss, Inc. [source]

Pathogenic cysteine mutations affect progranulin function and production of mature granulins

JOURNAL OF NEUROCHEMISTRY, Issue 5 2010
Jun Wang
J. Neurochem. (2010) 112, 1305,1315. Abstract Frontotemporal dementia with ubiquitin-positive inclusions (FTLD-U) can be caused by mutations in the progranulin gene (GRN). Progranulin (PGRN) is a cysteine-rich growth factor, which is proteolytically cleaved by elastase to produce several granulins (GRNs). All FTLD-U mutations in GRN characterized to date result in reduced secreted PGRN protein. We recently reported a Spanish family with progressive non-fluent aphasia and dementia in which a novel C521Y mutation segregates with disease. A second cysteine mutation (C139R) has also been reported to be disease specific. Allele-specific mRNA expression assays in brain reveal that the C521Y mutant allele is expressed at similar levels to the wild-type allele. Furthermore, plasma PGRN levels in C521Y carriers are comparable with non-carrier family relatives, suggesting that the mutation does not affect PGRN protein expression and secretion in vivo. Despite normal PGRN levels C521Y and C139R mutant GRNs show reduced neurite growth-stimulating activity in vitro. Further study revealed that these mutations also cause impaired cleavage of PGRN by elastase. Our data suggest that these mutations affect the function of full-length PGRN as well as elastase cleavage of PGRN into GRNs, leading to neurodegeneration. [source]

Frontotemporal lobar degeneration with ubiquitinated tau-negative inclusions and additional ,-synuclein pathology but also unusual cerebellar ubiquitinated p62-positive, TDP-43-negative inclusions

NEUROPATHOLOGY, Issue 4 2009
Andrew King
Mutations in the progranulin (PGRN) gene on chromosome 17 have been shown to be responsible for one non-tauopathy subtype of familial frontotemporal lobar degeneration , frontotemporal lobar degeneration with ubiquitinated, tau-negative inclusions (FTLD-U). Such cases have pathological similarities to sporadic cases with neuronal inclusions positive for ubiquitin, the ubiquitin binding protein, p62 and the newly recognised protein TDP-43 but negative for hyperphosphorylated (HP) tau. There has been a recent report on two families with a novel progranulin mutation where the neuropathology showed not only TDP-43 neuronal positivity but separate tau and/or ,-synuclein pathology. We describe an unusual case with some family history but no mutation in the progranulin gene. The pathological features were typical for FTLD-U but with additional significant ,-synuclein pathology, and unusual ubiquitin-positive, p62-positive, TDP-43-negative inclusions in the cerebellum. This case may represent a further pathological phenotype for familial FTLD-U. It also highlights the need for further investigations on the ubiquitin binding protein p62 as a marker in FTLD-U. It is certainly possible that the presence or absence of these ubiquitinated p62-positive yet TDP-43-negative cerebellar inclusions may act as a useful correlative factor in the future. [source]