Format

Send to

Choose Destination
Clin Interv Aging. 2018 Jul 31;13:1321-1329. doi: 10.2147/CIA.S170374. eCollection 2018.

A pathogenic PSEN2 p.His169Asn mutation associated with early-onset Alzheimer's disease.

Author information

1
Department of BioNano Technology, Gachon Medical Research Institute, Gachon University, Seongnam, South Korea, seong.an@gmail.com.
2
Department of Neurology, Seoul National University College of Medicine & Neurocognitive Behavior Center, Seoul National University Bundang Hospital, Seongnam, South Korea, neuroksy@snu.ac.kr.
#
Contributed equally

Abstract

Background:

Autosomal dominant early-onset Alzheimer's disease (EOAD) is genetically heterogeneous and has been associated with mutations in 3 different genes, coding for amyloid precursor protein (APP), presenilin 1 (PSEN1), and presenilin 2 (PSEN2). Most frequent cases are associated with mutations in the PSEN1 gene, whereas mutations in the APP and PSEN2 genes are rare.

Methods:

Patient who presented progressive memory decline in her 50s was enrolled in this study. A broad battery of neuropsychological tests and neuroimaging was applied to make the diagnosis. Genetic tests were performed in the patient to evaluate possible mutations using next-generation sequencing (NGS). The pathogenic nature of missense mutation and its 3D protein structure prediction were performed by in silico prediction programs.

Results:

A pathogenic mutation in the PSEN2 gene in a Korean patient associated with EOAD was identified. Targeted Next-generation sequencing and Sanger sequencing revealed a heterozygous C to A transition at position 505 (c.505C>A), resulting in a probably missense mutation at codon 169 (p.His169Asn) in PSEN2. PolyPhen-2 and SIFT software analyses predicted this mutation to be a probable damaging variant. This hypothesis was supported by the results of 3D in silico modelling analyses that predicted the p.His169Asn may result in major helix torsion due to histidine to asparagine substitution. Mutation may cause additional stresses with hydrophobic residues on the surface that interact inside the transmembrane domain III, which is a conserved domain in PSEN2 His169.

Conclusion:

These findings revealed that the p.His169Asn might be an important residue in PSEN2, which may alter the functions of PSEN2, suggesting its potential involvement with AD phenotype. Future functional studies are needed to evaluate the role of PSEN2 p.His169Asn mutation in AD disease progression.

KEYWORDS:

Alzheimer’s disease; next-generation sequencing; p.His169Asn mutation; presenilin-2

PMID:
30104866
PMCID:
PMC6074827
DOI:
10.2147/CIA.S170374
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Dove Medical Press Icon for PubMed Central
Loading ...
Support Center