長壽的秘訣？科學家稱，或許就藏在基因裡

Recently The Guardian has reported the following:

The secret to long life? It could be in the genes after all, say scientists

New study into ‘heritability’ shows that 50% of the variation in human lifespan could be down to genetics

The Guardian - Nicola Davis Science correspondent

Thu 29 Jan 2026 19.00 GMT

Some people who live to a great age put it down to an evening tot of whisky, others to staying out of trouble. Now scientists think they may have unlocked a key secret to long life – quite simply, genetics.

Writing in the journal Science, the researchers described how previous studies that had attempted to unpick the genetic component of human lifespan had not taken into account that some lives were cut short by accidents, murders, infectious diseases or other factors arising outside the body. Such “extrinsic mortality” increases with age, as people often become more frail.

Prof Uri Alon and colleagues at the Weizmann Institute of Science in Israel say the true genetic contribution to the variation in human lifespan has been masked.

The team looked at “heritability”, the proportion of change in a characteristic such as height, body weight or lifespan within a population that can be attributed to genetics rather than environmental factors. Previous studies for human lifespan have thrown up a wide range of values – with heritability ranging from 6% of the variation to 33%.

But Alon, who co-authored the research, and his colleagues said such figures were underestimates. “I hope this will inspire researchers to make a deep search for the genes that impact lifespan,” Alon said. “These genes will tell us the mechanisms that govern our internal clocks.

“These can one day be turned into therapy to slow down the rate of ageing and in that way slow down all age-related disease at once.”

The team created a mathematical model that takes into account extrinsic mortality and the impact of biological ageing, and calibrated it using correlations of lifespan from historical datasets of thousands of pairs of twins in Denmark and Sweden.

They removed the impact of extrinsic mortality to reveal the signal from biological ageing, which is caused by genetics. The results suggest about 50% of the variation in human lifespan is due to genetics – a figure the researchers said was on a par with that seen in wild mice in the laboratory.

The other 50% of variation in human lifespan, they said, was probably explained by factors such as random biological effects and environmental influences.

“That’s where we would expect to find all the usual suspects – lifestyle, diet, exercise, social relations, environment, and more,” said Ben Shenhar, who co-authored the research, adding that lifestyle and environment were likely to become more important as we age.

The team tested their results using data from a US study of siblings of centenarians, and found a heritability of lifespan of about 50%.

Further testing using another Swedish dataset revealed that as extrinsic mortality fell from the start of the 20th century – likely due to factors such as improvements in public health – the estimated genetic contribution to lifespan rose, supporting the idea that extrinsic mortality was a key factor when looking at heritability. The team also found the heritability of lifespan varied depending on the cause of death, such as cancer or dementia, and age.

Shenhar added that day-to-day experience showed genetics played an important role in longevity. “Around 20% of centenarians, for example, reach age 100 without any serious debilitating illnesses,” he said, adding that could suggest their genes had a protective effect. “Studies have been conducted to identify these protective genes, and many have been found, but surely there are many still left to discover,” he said.

While the new study does not take into account the influence that genes can have on the immune system, Prof Richard Faragher of the University of Brighton said the research suggested humans did not seem to be an outlier when it came to the heritability of lifespan.

“And that’s useful because it means humans look quite like a species that we study ageing in, [and] gives you a certain amount of confidence that interventions that will work in mice will carry over into humans,” he said.

Translation

長壽的秘訣？科學家稱，或許就藏在基因裡

一項關於「遺傳性」的新研究表明，人類壽命差異的50%可能源自於基因

有些長壽者將長壽歸功於睡前小酌一杯威士忌，有些人則認為長壽的秘訣在於遠離麻煩。如今，科學家認為他們可能已經揭開了長壽的關鍵秘密 - 其實很簡單，就是基因。

研究人員在《科學》雜誌上撰文指出，以往試圖揭示人類壽命遺傳因素的研究忽略了這樣一個事實：有些人因意外事故、謀殺、傳染病或其他體外因素而英年早逝。這種「外在死亡率」會隨著年齡的增長而增加，因為人們往往會趨向更加脆弱。

以色列Weizmann科學研究所的Uri Alon教授及其同事表示，真正的遺傳因素對人類壽命差異的貢獻一直被掩蓋。

該團隊研究了“遺傳性”，即在人群中，身高、體重或壽命等特徵變化中可歸咎於遺傳而非環境因素的比例。以往關於人類壽命的研究得出了各種各樣的數值 - 遺傳性佔變異因素的比例從6%到33%不等。

但作為研究的共同作者之一，Alon教授及其同事表示，這些數字被低估了。 Alon教授說: 「我希望這項研究能激勵研究人員深入探索影響壽命的基因」; 「這些基因將揭示控制我們生理時鐘的機制」。

“這些機制或許有一天能夠轉化為治療方法，從而減緩衰老速度，進而減緩所有與年齡相關的疾病。”

研究團隊創建了一個數學模型，該模型考慮了外在死亡和生物老化的影響，並使用來自丹麥和瑞典數千對雙胞胎的歷史數據, 利用期相關性對其進行校準。

他們剔除了外在死亡的影響，從而揭示了由遺傳因素導致的生物老化訊號。結果表明，人類壽命差異的約50%是由遺傳因素造成的 - 研究人員表示，這一比例與實驗室中觀察野生小鼠的結果一致。

他們表示，人類壽命差異的另外50%可能由隨機生物效應和環境影響等因素解釋。

該研究的合著者Ben Shenhar說道:「我們預計會在這裡找到所有常見的可疑因素 - 生活方式、飲食、運動、社會關係、環境等等」，並補充說，隨著年齡的增長，生活方式和環境可能會變得更加重要。

研究團隊利用美國一項針對百歲老人兄弟姊妹的研究數據檢驗了他們的結果，發現因遺傳而長壽約為佔 50%。

使用另一個瑞典數據集進行的進一步測試顯示，自 20 世紀初以來，外在死亡率有所下降。（這很可能是由於公共衛生水平的提高等因素），遺傳因素對壽命的貢獻估計值上升，這支持了外源性死亡率是影響遺傳因素的關鍵。研究團隊也發現，壽命的遺傳性會因死亡原因（如癌症或失智症）和年齡而異。

Shenhar補充說，日常經驗表明，遺傳在長壽中扮演著重要角色。 他說道:「例如，大約20%的百歲老人活到100歲時沒有任何嚴重的衰弱性疾病」，並補充說這可能表明他們的基因具有保護作用。他又說: 「一些研究來識別這些保護性基因已經開展，並且已經發現了很多，但肯定還有許多基因有待發現」。

雖然這項新研究沒有考慮基因對免疫系統的影響，布萊頓大學的Richard Faragher教授表示，這項研究表明，就壽命的遺傳性而言，人類似乎並非特例。

他說:「這很有用，因為它意味著人類與我們研究衰老的物種非常相似，[並且]讓我們有理由相信，在小鼠身上有效的干預措施也能在人類身上得到應用」。

So, now scientists think that a key secret to long life is genetics. Researchers described how previous studies that attempted to unpick the genetic component of human lifespan had not taken into account that some lives were cut short by accidents, murders, infectious diseases or other factors arising outside the body and thus underestimated the impact of heritability. Apparently, this is an interesting finding that may help our research to extend our lifespan in the future.