The ApoE4 isoform is associated with a 2-3 fold increased risk of Alzheimer's disease for the 3-4 genotype and an 8-10 fold increased risk for the 4-4 genotype.

“Chris Hemsworth it turns out is apoe44 so Chris asks in his accent what is the risk of Alzheimer's and Peter says 8 to 10 times increased risk”

“the literature said the four for patients relative to the three three patients have a twenty five fold increase I today we see that number I think continually being downward revised so for my four four patients the good news that I have three patients in my practice who are four four the good news for those patients is look these numbers are getting better and better I mean you and I I think offline would agree unofficially it might be closer to four to six x i don't even that you even even know optimistic well i'm just gonna be frank alzheimer's and eight bowie is confusing and having two copies of before does absolutely not mean you're gonna get the disease and it's a polygenic risk when it comes to the disease you know you can have two copies of you four but never have a family member and never get the disease I don't believe it's medically correct you know it's artists you know split hairs or whatever I don't even think you can say it's two percent or five percent or 20 percent or whatever percent higher how many fold whatever because you can't know until you know what the other person's genes are yeah it's very hard to do and I think the best that people are doing in these large population-based studies is saying acknowledging the heterogeneity of those other risk factors all things equal the last you know paper I read basically said eight to ten X so again maybe that's still an over estimate I believe it is an over estimate”

“the three fours now they represent quite a bit of people that's like twenty to twenty-five percent of population cell 25 in our cohort it's about forty ok which again makes sense you're over representing again they used to be represented as about a three to four X I mean I think today we're saying maybe a 2 X”

“you have the four for now that used to be reported as 1% of the population but I see that so often that I think that's closer to three or four percent of the population”

“you have two threes and two fours two fours are pretty rare about neutral risk my cousin's at two four I've seen two cases but it's pretty rare do we think that the two fours are at increased risk decreased risk because of the to increase risk because of the for all things equal similar ish two three three but a little worse yeah that's sort of my thinking”

“a33 could mean you did not get the four from mom or dad and life is beautiful maybe the risk is lower but if you have a three three and mom and dad were three three and they didn't have the four guess what they probably have another gene and I don't know what that gene is and I don't know what I'm up because you test the parents in that situation well it's tricky”

“the 3-4 seems to be associated with about a two to three-fold risk in alzheimer's disease and the 4-4 probably about an 8-12 fold or maybe eight to 10-fold increase in risk”

“ten years ago we thought that being homozygous for e4 so being in that roughly one percent of the population that has two copies of the e4 gene that was a death sentence as you noted earlier that's that's a person who's going to have alzheimer's disease by 60 and they're going to be dead by 70. it's there's no way out of that their their risk is deemed at about 20 fold that of the general population and then five years ago we looked at the data again and said you know it's still awful but it's not 20 times the risk of the e3 e3 it's 12 times the risk and then we look at the data again two years ago and you know it's still bad but it's it's maybe it's five times the risk”