Alzheimer's - Dementia, Author Interviews, Genetic Research, Mental Health Research / 23.05.2017
Familial History Improves Predictive Value of TOMM40 Gene in Alzheimer’s Disease
MedicalResearch.com Interview with:
Auriel Willette, M.S., Ph.D.
Assistant Professor
Departments of Food Science and Human Nutrition and Psychology
Iowa State University
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Translocase of Outer Mitochondrial Membrane 40 (TOMM40) is a gene that regulates the width of the outer mitochondrial pore, facilitating the transport of ribosomal pre-proteins into the inner mitochondrial matrix for translational modification into functional proteins. In 2010, Dr. Allen Roses, who discovered the Apolipoprotein E (APOE) gene, Dr. Michael Lutz, and other colleagues found that a variation in poly-T length at locus rs10524523 ('523) within intron 6 predicted Alzheimer's disease onset. Specifically, a "long" versus "short" poly-T length was related to earlier age of onset by 8 years.
However, several multi-cohort studies either failed to replicate the findings or found the opposite relationship, where a "long" or "very long" poly-T length was related to later age of onset. The literature has remained mixed to this day.
We were interested in testing factors that might change the relationship between TOMM40 and both cognitive decline and risk for having Alzheimer's disease. It is known that a family history (FH) of Alzheimer's disease has been associated with mitochondrial dysfunction. We reasoned, then, that FH may interact with TOMM40 to modulate how it was related to our outcomes of interest. We investigated this hypothesis in two separate cohorts: the Wisconsin Registry for Alzheimer's Prevention (WRAP), a late middle-aged cohort, and the Alzheimer's Disease Neuroimaging Initiative (ADNI), a well-characterized sample of aged participants from across the Alzheimer's spectrum.
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