Genome-wide analyses as part of the international FTLD-TDP whole-genome sequencing consortium reveals novel disease risk factors and increases support for immune dysfunction in FTLD.
Acta Neuropathol. 2019 Feb 9. doi: 10.1007/s00401-019-01962-9. [Epub ahead of print]
|Authors/Editors:||Pottier C, Ren Y, Perkerson RB 3rd, Baker M, Jenkins GD, van Blitterswijk M, DeJesus-Hernandez M, van Rooij JGJ, Murray ME, Christopher E, McDonnell SK, Fogarty Z, Batzler A, Tian S, Vicente CT, Matchett B, Öijerstedt L, Neumann M, Heutink P, Synofzik M, Wilke C, Prudlo J, Rizzu P, Simon-Sanchez J, Karydas AM, Hsiung GR, Seelaar H, Mol MO, Finger EC, Graff C, Öijerstedt L, Neumann M, Heutink P, Synofzik M, Wilke C, Prudlo J, Rizzu P, Simon-Sanchez J, Karydas AM, Hsiung GR, Seelaar H, Mol MO, Finger EC, Graff C, Öijerstedt L, Neumann M, Heutink P, Synofzik M, Wilke C, Prudlo J, Rizzu P, Simon-Sanchez J, Edbauer D, Roeber S, Diehl-Schmid J, Evers BM, King A, Mesulam MM, Weintraub S, Geula C, Bieniek KF, Petrucelli L, Ahern GL, Reiman EM, Woodruff BK, Caselli RJ, Huey ED, Farlow MR, Grafman J, Mead S, Grinberg LT, Josephs KA, Parisi JE, Knopman DS, Petersen RC, Hodges JR, Piguet O, Geier EG, Yokoyama JS, Rissman RA, Rogaeva E, Keith J, Zinman L, Tartaglia MC, Cairns NJ, Cruchaga C, Ghetti B, Kofler J, Lopez OL, Beach TG, Arzberger T, Rissman RA, Rogaeva E, Keith J, Zinman L, Tartaglia MC, Cairns NJ, Cruchaga C, Ghetti B, Kofler J, Lopez OL, Beach TG, Arzberger T, Herms J, Honig LS, Vonsattel JP, Halliday GM, Kwok JB, White CL 3rd, Gearing M, Glass J, Rollinson S, Pickering-Brown S, Rohrer JD, Trojanowski JQ, Van Deerlin V, Bigio EH, Troakes C, Al-Sarraj S, Asmann Y, Miller BL, Graff-Radford NR, Boeve BF, Seeley WW, Mackenzie IRA, van Swieten JC, Dickson DW, Biernacka JM, Rademakers R.|
Frontotemporal lobar degeneration with neuronal inclusions of the TAR DNA-binding protein 43 (FTLD-TDP) represents the most common pathological subtype of FTLD. We established the international FTLD-TDP whole-genome sequencing consortium to thoroughly characterize the known genetic causes of FTLD-TDP and identify novel genetic risk factors. Through the study of 1131 unrelated Caucasian patients, we estimated that C9orf72 repeat expansions and GRN loss-of-function mutations account for 25.5% and 13.9% of FTLD-TDP patients, respectively. Mutations in TBK1 (1.5%) and other known FTLD genes (1.4%) were rare, and the disease in 57.7% of FTLD-TDP patients was unexplained by the known FTLD genes. To unravel the contribution of common genetic factors to the FTLD-TDP etiology in these patients, we conducted a two-stage association study comprising the analysis of whole-genome sequencing data from 517 FTLD-TDP patients and 838 controls, followed by targeted genotyping of the most associated genomic loci in 119 additional FTLD-TDP patients and 1653 controls. We identified three genome-wide significant FTLD-TDP risk loci: one new locus at chromosome 7q36 within the DPP6 gene led by rs118113626 (p value = 4.82e - 08, OR = 2.12), and two known loci: UNC13A, led by rs1297319 (p value = 1.27e - 08, OR = 1.50) and HLA-DQA2 led by rs17219281 (p value = 3.22e - 08, OR = 1.98). While HLA represents a locus previously implicated in clinical FTLD and related neurodegenerative disorders, the association signal in our study is independent from previously reported associations. Through inspection of our whole-genome sequence data for genes with an excess of rare loss-of-function variants in FTLD-TDP patients (n ≥ 3) as compared to controls (n = 0), we further discovered a possible role for genes functioning within the TBK1-related immune pathway (e.g., DHX58, TRIM21, IRF7) in the genetic etiology of FTLD-TDP. Together, our study based on the largest cohort of unrelated FTLD-TDP patients assembled to date provides a comprehensive view of the genetic landscape of FTLD-TDP, nominates novel FTLD-TDP risk loci, and strongly implicates the immune pathway in FTLD-TDP pathogenesis.