Perhaps the "over 60" part is key -- the kin selection fitness value of individuals in hunter-gatherer tribes probably drops off pretty fast after 60, so there's not much selection pressure to fix this bad gene.

Other factors might be a modern environment, pollution, pathogens, etc.

I wonder to what degree genetic problems are being exacerbated by our modern lifestyle. Obesity, sedentary living, tremendous population density, etc. etc.

My grandfather-in-law was diagnosed with Macular Degeneration at around age 70. He had a mild case with slow progression. He was a retired Fire chief, tall, right handed, thin, and very active. Those factors might explain why his case was mild

/died of a sudden case of Valley Fever a few years later, nobody could believe it.

the kin selection fitness value of individuals in hunter-gatherer tribes probably drops off pretty fast after 60, so there's not much selection pressure to fix this bad gene.

even now, I doubt there's much, if any, selection pressure against this allele.

but why is this haplotype at 25%? is there something around this allele which was selected for? maybe it's agriculture....(?) ;-)

even now, I doubt there's much, if any, selection pressure against this allele.

I've read (anecdotally) that 60 is more or less the cut off point for natural selection in humans. Anything can genetically crap out after that point and natural selection is powerless to select against it.

It would be useful to determine whether this allele has any beneficial effects earlier in life. If it doesn't, and is essentially identical to alternative versions except for this specific effect (which is probably too good to be probable), it would be an excellent target for Gattaca-esque elimination.

Very interesting research on PXF (pseudoexfoliation glaucoma). If you are interested in seeing with this type of glaucoma looks like in vivo, you may be interested in seeing this microscope video:

Exfoliation glaucoma of the eye

Amazing that this phenotype has been linked to a single gene.