Comment by nerdralph

There's a lot of genes that impact lifespan, both good and bad. For example my father has hereditary hemochromatosis due to 2 copies of the HFE C282Y mutation. He was diagnosed in his 50's, so I'd expect the damage it did to his body to impact lifespan.

In my case I don't have it (I'm just a genetic carrier). If I did have the genotype and took the necessary dietary measures to avoid the phenotype, then it likely wouldn't impact lifespan.

On one hand you can argue a heritable disease like HHC has an impact on lifespan, but with genetic testing and treatment you can argue it doesn't impact lifespan (or it's impact is significantly mitigated).