1999
Year 19
Prof. Sid Gilman
Professor of Neurology
University of Michigan, USA
THEME: THE CHALLENGE OF ALZHEIMER’S DISEASE
The strongest risk factors are age, family history and Down’s syndrome. Weaker risk factors
include lower level of education, female gender, history of head injury, exposure to heavy
metals and other toxins. The risk of AD increases exponentially with age and approximately
doubles with each decade after the age of sixty five years. Genetic influences have received
much attention in recent times. The most common form of familial AD in the older age group
appears to be inherited as an autosomal dominant trait with increasing penetrance with ageing.
There is a strong relationship between the presence of apolipoprotein E polymorphism and the
risk of developing AD in this age group. Chromosome 19 contains the gene encoding
apolipoprotein E and presence of allele 4 of its three alleles increases the risk of AD. Early onset
familial AD accounts for less than 5% of the cases. It occurs from inheritance of a highly
penetrant autosomal dominant mutation in chromosome 21, 14 or 1, resulting in amyloid
deposition. Research is on to develop biomarkers that can be utilised for commercially available
diagnostic test kits to detect high risk potential for AD.
