The −48 C/T polymorphism in the presenilin 1 promoter is associated with an increased risk of developing Alzheimer's disease and an increased Aβ load in brain
- Jean-Charles Lamberta,
- David M A Mannb,
- Judith M Harrisa,
- Marie-Christine Chartier-Harlinc,
- Alistair Cummingd,
- John Coatesa,
- Helen Lemmond,
- David StClaird,
- Takeshi Iwatsuboe,
- Corinne Lendona
- aMolecular Psychiatry Department, Division of Neuroscience, Queen Elizabeth Psychiatry Hospital, University of Birmingham, Birmingham B15 2QZ, UK, bLaboratory Medicine Academic Group, Department of Medicine, Stopford Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK, cINSERM 508, Institut Pasteur de Lille, 1 rue du Professeur Calmette, BP 245, 59019 Lille Cédex, France, dDepartment of Mental Health, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK, eDepartment of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, University of Tokyo, Japan
- Dr Lendon, c.l.lendon{at}bham.ac.uk
- Revised 29 March 2001
- Accepted 3 April 2001
Abstract
Mutations in the presenilin 1 gene (PS1) account for the majority of early onset, familial, autosomal dominant forms of Alzheimer's disease (AD), whereas its role in other late onset forms of AD remains unclear. A −48 C/T polymorphism in the PS1 promoter has been associated with an increased genetic risk in early onset complex AD and moreover has been shown to influence the expression of the PS1 gene. This raises the possibility that previous conflicting findings from association studies with homozygosity for the PS1 intron 8 polymorphism might be the result of linkage disequilibrium with the –48 CC genotype. Here we provide further evidence of increased risk of AD associated with homozygosity for the −48 CC genotype (odds ratio=1.6). We also report a phenotypic correlation with Aβ40, Aβ42(43), and total Aβ load in AD brains. The −48 CC genotype was associated with 47% greater total Aβ load (p<0.003) compared to CT + TT genotype bearers. These results suggest that the –48 C/T polymorphism in thePS1 promoter may increase the risk of AD, perhaps by altering PS1 gene expression and thereby influencing Aβ load.
