학술논문

TMEM106B protects C9ORF72 expansion carriers against frontotemporal dementia
Document Type
article
Source
Acta Neuropathologica. 127(3)
Subject
Biomedical and Clinical Sciences
Neurosciences
Dementia
Frontotemporal Dementia (FTD)
Neurodegenerative
Alzheimer's Disease Related Dementias (ADRD)
Genetics
Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD)
ALS
Human Genome
Clinical Research
Rare Diseases
Acquired Cognitive Impairment
Brain Disorders
2.1 Biological and endogenous factors
Aetiology
Neurological
Adult
Age of Onset
Aged
Aged
80 and over
Alleles
C9orf72 Protein
Cohort Studies
DNA Repeat Expansion
DNA-Binding Proteins
Female
Frontotemporal Dementia
Genetic Predisposition to Disease
Genotype
Heterozygote
Humans
Male
Membrane Proteins
Middle Aged
Models
Genetic
Motor Neuron Disease
Nerve Tissue Proteins
Polymorphism
Single Nucleotide
Proteins
C9ORF72
TMEM106B
Frontotemporal dementia
Motor neuron disease
Amyotrophic lateral sclerosis
Disease modifier
Clinical Sciences
Neurology & Neurosurgery
Language
Abstract
Variants in transmembrane protein 106 B (TMEM106B) modify the disease penetrance of frontotemporal dementia (FTD) in carriers of progranulin (GRN) mutations. We investigated whether TMEM106B is also a genetic modifier of disease in carriers of chromosome 9 open reading frame 72 (C9ORF72) expansions. We assessed the genotype of 325 C9ORF72 expansion carriers (cohort 1), 586 FTD patients lacking C9ORF72 expansions [with or without motor neuron disease (MND); cohort 2], and a total of 1,302 controls for TMEM106B variants (rs3173615 and rs1990622) using MassArray iPLEX and Taqman genotyping assays. For our primary analysis, we focused on functional variant rs3173615, and employed a recessive genotypic model. In cohort 1, patients with C9ORF72 expansions showed a significantly reduced frequency of carriers homozygous for the minor allele as compared to controls [11.9 vs. 19.1 %, odds ratio (OR) 0.57, p = 0.014; same direction as carriers of GRN mutations]. The strongest evidence was provided by FTD patients (OR 0.33, p = 0.009) followed by FTD/MND patients (OR 0.38, p = 0.017), whereas no significant difference was observed in MND patients (OR 0.85, p = 0.55). In cohort 2, the frequency of carriers homozygous for the minor allele was not significantly reduced in patients as compared to controls (OR 0.77, p = 0.079); however, a significant reduction was observed when focusing on those patients with frontotemporal lobar degeneration and TAR DNA-binding protein 43 inclusions (FTLD-TDP; OR 0.26, p < 0.001). Our study identifies TMEM106B as the first genetic factor modifying disease presentation in C9ORF72 expansion carriers. Homozygosity for the minor allele protects carriers from developing FTD, but not from developing MND; similar effects are seen in FTLD-TDP patients with yet unknown genetic causes. These new findings show that the protective effects of TMEM106B are not confined to carriers of GRN mutations and might be relevant for prognostic testing, and as a promising therapeutic target for the entire spectrum of FTLD-TDP.