TAU haplotype and the Saitohin Q7R gene polymorphism do not influence CSF Tau in Alzheimer's disease and are not associated with frontotemporal dementia or Parkinson's disease.
BACKGROUND
Recent studies have described Saitohin(STH), a gene located in the human TAU gene. The corresponding protein shows a similar tissue expression to tau, which is involved in many neurodegenerative disorders including Alzheimer's disease (AD), frontotemporal dementia (FTD) and Parkinson's disease (PD). A single nucleotide polymorphism in the STH gene has been suggested to be involved in sporadic AD and is in complete linkage disequilibrium with the TAU haplotype H1.


OBJECTIVE
A case-control study was performed to further explore the possible involvement of the STH Q7R polymorphism and the extended TAU haplotype in AD, FTD or PD.


METHODS
Patients with AD (n = 398), FTD (n = 96) and PD (n = 105), and controls (n = 186) were genotyped for the STH polymorphism and/or the TAU haplotype. Genotype data were related to levels of total-tau, phospho-tau and Abeta(1-42) in cerebral spinal fluid (CSF) in more than 300 AD patients and to an amount of senile plaques and neurofibrillary tangles in the frontal cortex and hippocampus in patients with autopsy-confirmed AD.


RESULTS
The STH Q7R polymorphism and the TAU haplotype were in complete linkage disequilibrium in all patients (AD and FTD) and controls investigated for both genes. There were no significant differences in genotype or allele distributions in AD, FTD or PD cases compared to controls. Neither TAU haplotype nor STH influenced CSF levels of total-tau, phospho-tau and Abeta(1-42) significantly. In AD patients with neuropathological scores of plaque and tangles, no associations with TAU haplotype and STH were found.


CONCLUSIONS
We found no evidence that could support a major pathogenic role of STH and TAU haplotype in AD, FTD or PD.
Johansson
Annica
A
Department of Clinical Neuroscience, Unit of Neurochemistry, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. annica.johansson@clinchem.gu.se
Zetterberg
Henrik
H
Håkansson
Anna
A
Nissbrandt
Hans
H
Blennow
Kaj
K
D000368:Aged; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000235:genetics*; D016229:Amyloid beta-Peptides / Q000235:genetics; D001921:Brain / Q000378:metabolism / Q000503:physiopathology; D001923:Brain Chemistry / Q000235:genetics; D016022:Case-Control Studies; D004252:DNA Mutational Analysis; D003704:Dementia / Q000134:cerebrospinal fluid / Q000235:genetics*; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005820:Genetic Testing; D005838:Genotype; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D010300:Parkinson Disease / Q000134:cerebrospinal fluid / Q000235:genetics*; D010446:Peptide Fragments / Q000235:genetics; D011110:Polymorphism, Genetic / Q000235:genetics; D011237:Predictive Value of Tests; D016875:tau Proteins / Q000134:cerebrospinal fluid / Q000235:genetics*
D016229:Amyloid beta-Peptides; D005819:Genetic Markers; D010446:Peptide Fragments; C458340:STH protein, human; C075222:amyloid beta-protein (1-42); D016875:tau Proteins