title: SORL1 gene, plasma biomarkers, and the risk of Alzheimer's disease for the Han Chinese population in Taiwan.
abstract: The sortilin-related receptor 1 (SORL1) gene, regulating the trafficking and recycling of amyloid precursor protein, has been related to Alzheimer's disease (AD) and mild cognitive impairment (MCI). The aim of the present study was to investigate the relationship between SORL1 polymorphisms, plasma concentrations of amyloid-beta (Aβ) isoforms, and AD and MCI susceptibility for a Han Chinese population in Taiwan.
  
  
  
  Eight single-nucleotide polymorphisms (SNPs) in SORL1 and the apolipoprotein E gene (APOE) ε4 alleles were genotyped in 798 patients with AD, 157 patients with MCI, and 401 control subjects. Plasma concentrations of Aβ42, Aβ40, and neuropsychiatric tests for six different cognitive domains were examined.
  
  
  
  Among the eight tested SNPs, SORL1 rs1784933 was most significantly associated with AD and MCI in our population. The G allele of rs1784933 exerted a protective effect and was associated with a reduced risk of AD (odds ratio [OR] = 0.75, p = 0.004) and MCI (OR = 0.69, p = 0.013). The significance remained after we adjusted for age, sex, and APOE ε4 alleles. For the overall participants, the plasma concentrations of Aβ42 were nominally significant for subjects carrying the rs1784933 G allele having a lower level than those without the G allele (p = 0.046). There was a similar trend for the G allele carriers to have a lower plasma Aβ40 level than noncarriers, but this was not significant. The nonsynonymous SNP rs2298813 was also related to a lower disease risk when AD and MCI were combined as a group (OR = 0.76, p = 0.035). However, there was no association between SORL1 genotypes and any of the six cognitive tests.
  
  
  
  Findings from our study provide support for the effect of SORL1 gene on the disease risks and pathognomonic surrogates of AD/MCI. The interaction between SORL1 polymorphisms and Aβ formation requires further study.
authors.affiliation: Department of Neurology, Neurological Institute, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Section 4, Taichung, 40705, Taiwan.
authors.forename: Cheng-Ta
authors.initials: CT
authors.lastname: Chou
authors.affiliation: Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Section 2, Shipai Road, Beitou District, Taipei City, 11217, Taiwan.|Department of Neurology, Faculty of Medicine, National Yang-Ming University, No. 155, Section 2, Li-Nong Street, Taipei, 11217, Taiwan.
authors.forename: Yi-Chu
authors.initials: YC
authors.lastname: Liao
authors.affiliation: Department of Neurology, Neurological Institute, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Section 4, Taichung, 40705, Taiwan.|Department of Neurology, Faculty of Medicine, National Yang-Ming University, No. 155, Section 2, Li-Nong Street, Taipei, 11217, Taiwan.|Institute of Clinical Medicine, National Yang-Ming University, No. 155, Section 2, Li-Nong Street, Taipei, 11217, Taiwan.
authors.forename: Wei-Ju
authors.initials: WJ
authors.lastname: Lee
authors.affiliation: Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Section 2, Shipai Road, Beitou District, Taipei City, 11217, Taiwan. sjwang@vghtpe.gov.tw.|Department of Neurology, Faculty of Medicine, National Yang-Ming University, No. 155, Section 2, Li-Nong Street, Taipei, 11217, Taiwan. sjwang@vghtpe.gov.tw.|Brain Research Center, School of Medicine, National Yang-Ming University, No. 155, Section 2, Linong Street, Taipei, 11217, Taiwan. sjwang@vghtpe.gov.tw.
authors.forename: Shuu-Jiun
authors.initials: SJ
authors.lastname: Wang
authors.affiliation: Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Section 2, Shipai Road, Beitou District, Taipei City, 11217, Taiwan. stellafuh@gmail.com.|Department of Neurology, Faculty of Medicine, National Yang-Ming University, No. 155, Section 2, Li-Nong Street, Taipei, 11217, Taiwan. stellafuh@gmail.com.|Brain Research Center, School of Medicine, National Yang-Ming University, No. 155, Section 2, Linong Street, Taipei, 11217, Taiwan. stellafuh@gmail.com.
authors.forename: Jong-Ling
authors.identifier: 0000-0001-9135-3351
authors.initials: JL
authors.lastname: Fuh
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood / Q000453:epidemiology / Q000208:ethnology / Q000235:genetics; D016229:Amyloid beta-Peptides / Q000097:blood*; D001057:Apolipoproteins E / Q000235:genetics; D044466:Asian People / Q000208:ethnology / Q000235:genetics; D060825:Cognitive Dysfunction / Q000097:blood / Q000453:epidemiology / Q000208:ethnology / Q000235:genetics; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D026502:LDL-Receptor Related Proteins / Q000235:genetics*; D015810:Linkage Disequilibrium; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics*; D008609:Mental Status Schedule; D009483:Neuropsychological Tests; D010446:Peptide Fragments / Q000097:blood*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D018709:Statistics, Nonparametric; D013624:Taiwan / Q000453:epidemiology / Q000208:ethnology
chemical_list: D016229:Amyloid beta-Peptides; D001057:Apolipoproteins E; D026502:LDL-Receptor Related Proteins; D026901:Membrane Transport Proteins; D010446:Peptide Fragments; C102582:SORL1 protein, human; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42)
keywords: Alzheimer’s disease; Amyloid-beta; Plasma biomarkers; Polymorphisms; SORL1 gene