Austin Health

Title
Clinical impact of whole-genome sequencing in patients with early-onset dementia.
Publication Date
2022-07-29
Author(s)
Huq, Aamira J
Thompson, Bryony
Bennett, Mark F
Bournazos, Adam
Bommireddipalli, Shobhana
Gorelik, Alexandra
Schultz, Joshua
Sexton, Adrienne
Purvis, Rebecca
West, Kirsty
Cotter, Megan
Valente, Giulia M
Hughes, Andrew J
Riaz, Moeen
Walsh, Maie
Farrand, Sarah
Loi, Samantha M
Kilpatrick, Trevor
Brodtmann, Amy
Darby, David G
Eratne, Dhamidhu
Walterfang, Mark
Delatycki, Martin B
Storey, Elsdon
Fahey, Michael
Cooper, Sandra
Lacaze, Paul
Masters, Colin L
Velakoulis, Dennis
Bahlo, Melanie
James, Paul A
Winship, Ingrid
Subject
American College of Medical Genetics and Genomics
Clinical Genetics
Dementia Genetics
Early Onset Dementia
Medical Genetics
Neurogenetics
Short Tandem Repeat Analysis
Structural Variant analysis
Whole Genome Sequencing
Type of document
Journal Article
OrcId
http://orcid.org/0000-0003-2341-2932
http://orcid.org/0000-0001-9466-2862
http://orcid.org/0000-0002-8769-2569
http://orcid.org/0000-0002-1449-2515
http://orcid.org/0000-0002-7660-8800
http://orcid.org/0000-0003-3072-7940
DOI
10.1136/jnnp-2021-328146
Abstract
In the clinical setting, identification of the genetic cause in patients with early-onset dementia (EOD) is challenging due to multiple types of genetic tests required to arrive at a diagnosis. Whole-genome sequencing (WGS) has the potential to serve as a single diagnostic platform, due to its superior ability to detect common, rare and structural genetic variation. WGS analysis was performed in 50 patients with EOD. Point mutations, small insertions/deletions, as well as structural variants (SVs) and short tandem repeats (STRs), were analysed. An Alzheimer's disease (AD)-related polygenic risk score (PRS) was calculated in patients with AD. Clinical genetic diagnosis was achieved in 7 of 50 (14%) of the patients, with a further 8 patients (16%) found to have established risk factors which may have contributed to their EOD. Two pathogenic variants were identified through SV analysis. No expanded STRs were found in this study cohort, but a blinded analysis with a positive control identified a C9orf72 expansion accurately. Approximately 37% (7 of 19) of patients with AD had a PRS equivalent to >90th percentile risk. WGS acts as a single genetic test to identify different types of clinically relevant genetic variations in patients with EOD. WGS, if used as a first-line clinical diagnostic test, has the potential to increase the diagnostic yield and reduce time to diagnosis for EOD.
Link
Citation
Journal of neurology, neurosurgery, and psychiatry 2022; online first: 29 July
Jornal Title
Journal of neurology, neurosurgery, and psychiatry

Files:

NameSizeformatDescriptionLink