Mendelian adult-onset leukodystrophy genes in Alzheimer's disease: critical influence of CSF1R and NOTCH3.

Abstract

Mendelian adult-onset leukodystrophies are a spectrum of rare inherited progressive neurodegenerative disorders affecting the white matter of the central nervous system. Among these, cerebral autosomal dominant and recessive arteriopathy with subcortical infarcts and leukoencephalopathy, cerebroretinal vasculopathy, metachromatic leukodystrophy, hereditary diffuse leukoencephalopathy with spheroids, and vanishing white matter disease present with rapidly progressive dementia as dominant feature and are caused by mutations in NOTCH3, HTRA1, TREX1, ARSA, CSF1R, EIF2B1, EIF2B2, EIF2B3, EIF2B4, and EIF2B5, respectively. Given the rare incidence of these disorders and the lack of unequivocally diagnostic features, leukodystrophies are frequently misdiagnosed with common sporadic dementing diseases such as Alzheimer's disease (AD), raising the question of whether these overlapping phenotypes may be explained by shared genetic risk factors. To investigate this intriguing hypothesis, we have combined gene expression analysis (1) in 6 different AD mouse strains (APPPS1, HOTASTPM, HETASTPM, TPM, TAS10, and TAU) at 5 different developmental stages (embryo [E15], 2, 4, 8, and 18 months), (2) in APPPS1 primary cortical neurons under stress conditions (oxygen-glucose deprivation) and single-variant-based and single-gene-based (c-alpha test and sequence kernel association test (SKAT)) genetic screening in a cohort composed of 332 Caucasian late-onset AD patients and 676 Caucasian elderly controls. Csf1r was significantly overexpressed (log2FC > 1, adj. p-value < 0.05) in the cortex and hippocampus of aged HOTASTPM mice with extensive Aβ dense-core plaque pathology. We identified 3 likely pathogenic mutations in CSF1R TK domain (p.L868R, p.Q691H, and p.H703Y) in our discovery and validation cohort, composed of 465 AD and mild cognitive impairment (MCI) Caucasian patients from the United Kingdom. Moreover, NOTCH3 was a significant hit in the c-alpha test (adj p-value = 0.01). Adult-onset Mendelian leukodystrophy genes are not common factors implicated in AD. Nevertheless, our study suggests a potential pathogenic link between NOTCH3, CSF1R, and sporadic late-onset AD, which warrants further investigation.

• Authors: Celeste Sassi, Michael A Nalls, Perry G Ridge, Jesse R Gibbs, Michelle K Lupton, Claire Troakes, Katie Lunnon, Safa Al-Sarraj, Kristelle S Brown, Christopher Medway, Jenny Lord, James Turton, Jose Bras, ARUK Consortium, Sonja Blumenau, Mareike Thielke, Christa Josties, Dorette Freyer, Annette Dietrich, Monia Hammer, Michael Baier, Ulrich Dirnagl, Kevin Morgan, John F Powell, John S Kauwe, Carlos Cruchaga, Alison M Goate, Andrew B Singleton, Rita Guerreiro, Angela Hodges, John Hardy
• Journal: Neurobiology of aging (Neurobiol Aging) Vol. 66 Pg. 179.e17-179.e29 (06 2018) ISSN: 1558-1497 [Electronic] United States
• PMID: 29544907 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, N.I.H., Intramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Chemical References

• CSF1R protein, human
• NOTCH3 protein, human
• Receptor, Notch3
• Receptors, Granulocyte-Macrophage Colony-Stimulating Factor

Topics

• Aged
• Aged, 80 and over
• Aging (genetics, metabolism)
• Alzheimer Disease (genetics)
• Animals
• Cerebral Cortex (metabolism)
• Cohort Studies
• Female
• Genetic Association Studies
• Hippocampus (metabolism)
• Humans
• Leukodystrophy, Metachromatic (genetics)
• Male
• Mice
• Middle Aged
• Mutation
• Receptor, Notch3 (genetics)
• Receptors, Granulocyte-Macrophage Colony-Stimulating Factor (genetics)
• Risk Factors
• White People