PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-4 (4)
 

Clipboard (0)
None
Journals
Year of Publication
Document Types
1.  Prominent Phenotypic Variability Associated with Mutations in Progranulin 
Neurobiology of aging  2007;30(5):739-751.
Mutations in progranulin (PGRN) are associated with frontotemporal dementia with or without parkinsonism. We describe the prominent phenotypic variability within and among eight kindreds evaluated at Mayo Clinic Rochester and/or Mayo Clinic Jacksonville in whom mutations in PGRN were found. All available clinical, genetic, neuroimaging and neuropathologic data was reviewed. Age of onset ranged from 49 to 88 years and disease duration ranged from 1 to 14 years. Clinical diagnoses included frontotemporal dementia (FTD), primary progressive aphasia, FTD with parkinsonism, parkinsonism, corticobasal syndrome, Alzheimer’s disease, amnestic mild cognitive impairment, and others. One kindred exhibited maximal right cerebral hemispheric atrophy in all four affected individuals, while another had maximal left hemisphere involvement in all three of the affected. Neuropathologic examination of 13 subjects revealed frontotemporal lobar degeneration with ubiquitin-positive inclusions plus neuronal intranuclear inclusions in all cases. Age of onset, clinical phenotypes and MRI findings associated with most PGRN mutations varied significantly both within and among kindreds. Some kindreds with PGRN mutations exhibited lateralized topography of degeneration across all affected individuals.
doi:10.1016/j.neurobiolaging.2007.08.022
PMCID: PMC3164546  PMID: 17949857
Frontotemporal dementia; FTDP-17; Progranulin; PGRN; MRI
2.  Alzheimer's Disease-Like Phenotype Associated With the c.154delA Mutation in Progranulin 
Archives of neurology  2010;67(2):171-177.
Objective
To characterize a kindred with a familial neurodegenerative disorder associated with a mutation in progranulin (PGRN), emphasizing the unique clinical features in this kindred.
Design
Clinical, radiologic, pathologic, and genetic characterization of a kindred with a familial neurodegenerative disorder.
Setting
Multispecialty group academic medical center.
Patients
Affected members of a kindred with dementia +/- parkinsonism associated with a unique mutation in PGRN.
Main Outcome Measure
Genotype-phenotype correlation.
Results
Ten affected individuals were identified, among whom six presented with initial amnestic complaints resulting in initial diagnoses of AD or amnestic mild cognitive impairment (MCI). A minority of individuals presented with features characteristic of FTD. The ages of onset of generation II (mean 75.8 years, range 69-80 years) were far greater than those of generation III (mean 60.7 years, range 55-66 years). The pattern of cerebral atrophy varied widely among affected individuals. Neuropathology in six individuals showed frontotemporal lobar degeneration with ubiquitin positive neuronal cytoplasmic and intranuclear inclusions (FTLD-U + NII). PGRN analysis revealed a single base pair deletion in exon 2 (c.154delA), causing a frameshift (p.Thr52Hisfs×2) and therefore creation of a premature termination codon and likely null allele.
Conclusions
We describe a large kindred in which the majority of affected individuals had clinical presentations resembling AD or amnestic MCI in association with a mutation in PGRN and underlying FTLD-U + NII neuropathology. This is in distinct contrast to previously reported kindreds, where clinical presentations have typically been within the spectrum of FTLD. The basis for the large difference in age of onset between generations will require further study.
doi:10.1001/archneurol.2010.113
PMCID: PMC2902004  PMID: 20142525
MRI; progranulin; frontotemporal dementia; PGRN
3.  Refining FTDP-17: Introducing FTDP-17(MAPT) and FTDP-17(PGRN) 
Archives of neurology  2008;65(4):460-464.
Frontotemporal dementia and parkinsonism (FTDP) is a major neurodegenerative syndrome, particularly for those with symptoms beginning before age 65. A spectrum of degenerative disorders can present as sporadic or familial FTDP. Mutations in the gene encoding the microtubule associated protein tau (MAPT) on chromosome 17 have been found in many kindreds with familial FTDP. Several other kindreds with FTDP had been linked to chromosome 17, but they had ubiquitin-positive inclusions rather than tauopathy pathology, and no mutations in MAPT. This conundrum was solved over this past year with the identification of mutations in the gene encoding progranulin (PGRN), which is only 1.7 Mb centromeric to MAPT on chromosome 17. In this review, we compare and contrast the demographic, clinical, radiologic, neuropathologic, genetic, and pathophysiologic features in patients with FTDP linked to mutations in MAPT and PGRN, highlighting the many similarities but also a few important differences. The findings provide an intriguing oddity of nature in which two genes can cause a similar phenotype through apparently different mechanisms yet reside so near to each other on the same chromosome.
doi:10.1001/archneur.65.4.460
PMCID: PMC2746630  PMID: 18413467
frontotemporal dementia; parkinsonism; progranulin; tau; PGRN; MAPT
4.  Novel Mutations in TARDBP (TDP-43) in Patients with Familial Amyotrophic Lateral Sclerosis 
PLoS Genetics  2008;4(9):e1000193.
The TAR DNA-binding protein 43 (TDP-43) has been identified as the major disease protein in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin inclusions (FTLD-U), defining a novel class of neurodegenerative conditions: the TDP-43 proteinopathies. The first pathogenic mutations in the gene encoding TDP-43 (TARDBP) were recently reported in familial and sporadic ALS patients, supporting a direct role for TDP-43 in neurodegeneration. In this study, we report the identification and functional analyses of two novel and one known mutation in TARDBP that we identified as a result of extensive mutation analyses in a cohort of 296 patients with variable neurodegenerative diseases associated with TDP-43 histopathology. Three different heterozygous missense mutations in exon 6 of TARDBP (p.M337V, p.N345K, and p.I383V) were identified in the analysis of 92 familial ALS patients (3.3%), while no mutations were detected in 24 patients with sporadic ALS or 180 patients with other TDP-43–positive neurodegenerative diseases. The presence of p.M337V, p.N345K, and p.I383V was excluded in 825 controls and 652 additional sporadic ALS patients. All three mutations affect highly conserved amino acid residues in the C-terminal part of TDP-43 known to be involved in protein-protein interactions. Biochemical analysis of TDP-43 in ALS patient cell lines revealed a substantial increase in caspase cleaved fragments, including the ∼25 kDa fragment, compared to control cell lines. Our findings support TARDBP mutations as a cause of ALS. Based on the specific C-terminal location of the mutations and the accumulation of a smaller C-terminal fragment, we speculate that TARDBP mutations may cause a toxic gain of function through novel protein interactions or intracellular accumulation of TDP-43 fragments leading to apoptosis.
Author Summary
The abnormal accumulation of disease proteins in neuronal cells of the brain is a characteristic feature of many neurodegenerative diseases. Rare mutations in the genes that encode the accumulating proteins have been identified in these disorders and are crucial for the development of cell and animal models used to study neurodegeneration. Recently, the TAR DNA-binding protein 43 (TDP-43) was identified as the disease accumulating protein in patients with frontotemporal lobar degeneration with ubiquitin inclusions (FTLD-U) and in amyotrophic lateral sclerosis (ALS). TDP-43 was also found in the brains of 20–30% of patients with Alzheimer's disease (AD). Here, we evaluated whether mutations in TDP-43 cause disease in a cohort of 296 patients presenting with FTLD, ALS or AD. We identified three missense mutations in three out of 92 familial ALS patients (3.3%), and no mutations in AD or FTLD patients. All the identified mutations clustered in exon 6, which codes for a highly conserved region in the C-terminal part of the TDP-43 protein, which is known to be involved in the interaction of TDP-43 with other proteins. We conclude that mutations in TDP-43 are a rare cause of familial ALS, but so far are not found in other neurodegenerative diseases.
doi:10.1371/journal.pgen.1000193
PMCID: PMC2527686  PMID: 18802454

Results 1-4 (4)