This clip is from episode #202, Peter on nutrition, disease prevention, sleep, and more, originally released on April 11, 2022.
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Show Notes
Alzheimer’s disease: genes that modify risk associated with the APOE4 variant [40:15]
Changes in thought related to Alzheimer’s disease: When it comes to Alzheimer’s disease, Peter’s focus on genes outside of APOE is now pretty significant
- It turns out that there are a lot of genes that seem to modify the risk of APOE
- APOE has three subtypes, e2, e3, and e4
- Everyone has a pair meaning there are six possible combinations
- The fourth isoform (e4) is the high risk one
- If you’re a e2/e4 it seems to, more or less, be a wash with maybe slight increase in risk
- The e3/e4 seems to be associated with about a 2x-3x increase in risk in Alzheimer’s disease
- The e4/e4 probably has about an 8x-12x increase in risk
- But even though everything above is true at the population level, it doesn’t explain what happens at the individual level
- There are some individuals who walk around with e4/e4 who don’t seem to get Alzheimer’s disease or if they do, they get it very late in life
Genes that modify the risk of the e4 variant
- It turns out that there are a bunch of other genes that we’re now starting to understand, modify the risk of e4 (some genes make it more significant, some genes make it less)
- So there are certain haplotypes of the TOMM40 gene that amplify risk
- There are certain mitochondrial haplotypes that amplify risk
- One of the most exciting genes is the Klotho modifier
- KL-VS is the modified snip of klotho that actually seems to erase all of the downside of APOE4
- So APOE4 people who have this klotho subtype have baseline risk
Prospects of identifying these genes in individuals
- Unfortunately the ways to measure these other genes, it’s very challenging and we have to do it by brute force today
- it takes a lot of time and costs a lot of money to take a whole genome sequence and do the search for all of these other subtypes
- A big step in the right direction here is going to be getting more data and getting those data for less than $20,000 per person.
- When might this be practical to do for people?
- Probably sooner than 10 years from now
- This is a solvable problem technically speaking, it’s just about throwing enough dollars at it
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