Amazing stuff! One reason why twin studies are so important!
"A new study points to a larger role for genetics than previous research had indicated, estimating the contribution of genes to determining human lifespan at about 50%. That is roughly double what prior research concluded, and it mirrors the findings of lifespan studies in laboratory animals. ..."
"... Surprisingly, for decades scientists believed that the heritability of human lifespan was relatively low compared to other human traits, standing at just 20 to 25 percent; some recent large-scale studies even placed it below 10 percent. ..."
From the editor's summary and abstract:
"Editor’s summary
... However, this is a difficult topic to study because it takes a long time to collect data on human life spans, and many different factors can contribute to mortality. One key distinction is between extrinsic mortality (violence, accidents, infections, etc.) and intrinsic mortality due to genetic mutations and/or aging-related diseases.
Shenhar et al. analyzed more than a century’s worth of data from three different Scandinavian twin cohorts and concluded that the current estimates of longevity heritability are much too low (see the Perspective by Bakula and Scheibye-Knudsen). In the late 1800s and early 1900s, when these study cohorts were born, extrinsic causes played a large role in mortality, but once those are excluded, longevity appears to be about 50% heritable, similar to many other traits. ...
Abstract
How heritable is human life span? If genetic heritability is high, longevity genes can reveal aging mechanisms and inform medicine and public health. However, current estimates of heritability are low—twin studies show heritability of only 20 to 25%, and recent large pedigree studies suggest it is as low as 6%.
Here we show that these estimates are confounded by extrinsic mortality—deaths caused by extrinsic factors such as accidents or infections. We use mathematical modeling and analyses of twin cohorts raised together and apart to correct for this factor, revealing that heritability of human life span due to intrinsic mortality is above 50%. Such high heritability is similar to that of most other complex human traits and to life-span heritability in other species."
Rethinking Longevity: Genes Matter More than We Thought (original news release) "Weizmann Institute study finds genetic contribution to human lifespan is about 50 percent – more than double previous estimates"
Rethinking the heritability of aging (open access) "The genetic contribution to human longevity is greater than previously thought"
Heritability of intrinsic human life span is about 50% when confounding factors are addressed (open access)
Credits: The Flyover
Fig. 1. Extrinsic mortality masks life-span correlations in twin cohorts.
Fig. 2. Life-span heritability increases when accounting for extrinsic mortality.
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