The clinical utility of gene testing for Alzheimer’s disease

Emily R Atkins,Peter K Panegyres

doi:10.4081/ni.2011.e1

Emily R Atkins, Peter K Panegyres

Open Access

https://doi.org/10.4081/ni.2011.e1

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Abstract

Alzheimer's disease (AD) is the largest cause of dementia, affecting 35.6 million people in 2010. Amyloid precursor protein, presenilin 1 and presenilin 2 mutations are known to cause familial early-onset AD, whereas apolipoprotein E (APOE) ε4 is a susceptibility gene for late-onset AD. The genes for phosphatidylinositol-binding clathrin assembly protein, clusterin and complement receptor 1 have recently been described by genome-wide association studies as potential risk factors for late-onset AD. Also, a genome association study using single neucleotide polymorphisms has identified an association of neuronal sortilin related receptor and late-onset AD. Gene testing, and also predictive gene testing, may be of benefit in suspected familial early-onset AD however it adds little to the diagnosis of late-onset AD and does not alter the treatment. We do not recommend APOE ε4 genotyping.

Highlights

(SNPs) has identified an association of neuronal sortilin related receptor (SORL1) and Key words: Alzheimer’s disease, gene testing
Genetic testing may be of benefit in this situation as the identification of the specific mutation in affected family members will confirm the diagnosis of familial early onset Alzheimer’s disease (AD).[4]
At least one instance of this has been reported in the literature, with a healthy child born.[10] binding protein 2(GAB2), bridging integrator 1 (BIN1), exocyst component 3-like 2 (EXOC3L2) and methylenetetrahydrofolate dehydrogenase (NAPD+ dependent) 1-like (MTHFD1L) have been identified as associated with the development of AD, but have been replicated with mixed results.[15,16,17]

Summary

Laboratory accreditation and DNA result disclosure

DNA testing for patients with suspected AD should always take place in an appropriately accredited laboratory. Whilst the accreditation requirements vary in each nation, the testing should be carried out in a reputable laboratory with quality controls in place to ensure accuracy.[4,9,24] The US NIH Genetic Testing Registry, which is expected to become operational in the near future, will address the utility and availability of genetic tests and make this information publicly available, it will be relying on genetic testing providers to voluntarily submit information.[25] The success of this registry will become evident in time. Direct to consumer (DTC) genetic testing is not recomthe risk of adverse reactions, such as psychiatric hospitalization and suicide attempts.[4] This method as has been successful with Huntington’s disease.[29]

Conclusions

Current status on Alzheimer disease