title: The extended tau haplotype and the age of onset of dementia in Down syndrome.
abstract: OBJECTIVE
  Most people with Down syndrome (DS) develop Alzheimer's disease (AD). The extended tau haplotype has been linked to AD. In this study, we examined the haplotype's effect on the age of onset of AD in DS.
  
  
  METHODS
  People with DS were assessed for dementia. Genotyping was performed for the extended tau haplotype, APOE and a polymorphism in APP, attt(5-8).
  
  
  RESULTS
  Haplotype frequencies vary between those developing AD before 45 and those developing dementia after this age (p = 0.03). H1/H2 individuals are more likely to develop dementia before 45 than H1/H1 individuals (OR = 3, 95% CI = 1.01-8.91).
  
  
  CONCLUSIONS
  Even in a condition driven by excess amyloid pathology, factors affecting tau are also important and should be considered as potential treatment targets.
authors.affiliation: Wolfson Centre for Age-Related Disease, Guy's Campus, King's College London, London, UK. emma.3.jones@kcl.ac.uk
authors.forename: Emma L
authors.initials: EL
authors.lastname: Jones
authors.forename: Marisa
authors.initials: M
authors.lastname: Margallo-Lana
authors.forename: Vee P
authors.initials: VP
authors.lastname: Prasher
authors.forename: Clive G
authors.initials: CG
authors.lastname: Ballard