Copy Number Variations Correlate With Mortality Rates
A copy number variation is either a large deletion or repeat of a sequence in your DNA. We all have them, and some people have more than others:
Copy-number variants (CNVs) are a source of genetic variation that increasingly are associated with human disease. However, the role of CNVs in human lifespan is to date unknown. To identify CNVs that influence mortality at old age, we analyzed genome-wide CNV data in 5178 participants of Rotterdam Study (RS1) and positive findings were evaluated in 1714 participants of the second cohort of the Rotterdam Study (RS2) and in 4550 participants of Framingham Heart Study (FHS). First, we assessed the total burden of rare (frequency <1%) and common (frequency >1%) CNVs for association with mortality during follow-up. ... We observed that the burden of common but not of rare CNVs influences mortality. ... A higher burden of large (≥500 kb) common deletions associated with 4% higher mortality.
We might speculate on what this means - and it's interesting to do so in light of the present debate over the role of nuclear DNA damage in aging. Is having generally more ragged DNA a bad thing in and of itself, or is it instead a marker for poor quality in other important biological processes, such that the DNA repair and copy checking mechanisms that exist to prevent this sort of issue from coming about in the first place? Only a handful of CNVs have been linked to raised risk of specific diseases, but that there is a general correlation with mortality rate suggests that researchers will find many more specific issues and areas of enhanced risk if they go looking for them.
Fortunately, the long age in which we humans were at the complete mercy of our inherited DNA is coming to a close - it'll be a fading memory only a century from now, something to look back on with mild horror, much as we look back on the comparatively recent ages in which infectious disease was a scourge. One of the great benefits of biotechnology is that every advance will allows the medical community to balance a small part of the genetic heritage we came into this world with. Some people enter the game with a bad hand: that matters less now than it did in the past, and it won't be too many decades more before it hardly matters at all - the sooner the better, I say.