一種用人類年齡計算狗狗年齡的新方法

一種用人類年齡計算狗狗年齡的新方法

People used to think that to get a rough equivalent of your dog's age in human years, you just multiplied by seven. But there was really no science behind the equation. The theory was that dogs lived about 10 years and people about 70, so divide and multiply.

人們過去認為，要得到相當(dāng)于狗的年齡(以人類的年齡計算)的大致數(shù)字，只需乘以7即可。但在這個等式背后真的沒有任何科學(xué)依據(jù)。他們的理論是，狗活了大約10年，人活了大約70年，所以用乘、除計算。

A new study finds dogs mirror human aging in the early and late parts of their lives. (Photo: Branislav Nenin/Shutterstock)

But researchers have come up with a new formula to convert dog years to people years based on how canine DNA changes over time.

但研究人員根據(jù)犬類DNA隨時間的變化，提出了一個新的公式，可以把狗的年齡換算成人的年齡。

Geneticists at the University of California, San Diego, used a process called DNA methylation. As animals get older, DNA picks up chains of atoms called methyl groups. Because methylation happens steadily with aging, researchers can use it to estimate age in humans, according to Smithsonian. This has been called the “epigenetic clock.”

加州大學(xué)圣地亞哥分校的遺傳學(xué)家使用了一種叫做DNA甲基化的方法。隨著動物年齡的增長，DNA會捕捉到稱為甲基的原子鏈。根據(jù)史密森尼的研究，由于甲基化是隨著年齡的增長而穩(wěn)定發(fā)生的，研究人員可以用它來估計人類的年齡。這被稱為“表觀遺傳鐘”。

In the new paper, published in pre-print bioRxiv ahead of peer review, researchers compared the epigenetic clock in people to dogs. Although life spans in dogs vary so much by breed, they still follow a similar developmental trajectory. They reach puberty at around 10 months and die before age 20, points out Science.

在同行評審之前發(fā)表在bioRxiv預(yù)印本上的這篇新論文中，研究人員將人與狗的表觀遺傳時鐘進行了比較。盡管不同品種的狗壽命差異很大，但它們?nèi)匀蛔裱嗨频陌l(fā)展軌跡。他們在10個月左右進入青春期，并在20歲之前死亡，科學(xué)雜志指出。

For ease in research, the researchers focused on one breed, studying 104 Labrador retrievers from 4 weeks to 16 years old. They compared the canine data to methylation profiles of 320 people from age 1 to 103 years old, as well as 133 mice, reports Michelle Starr at Science Alert.

為了便于研究，研究人員集中在一個品種上，研究了104只從4周到16歲的拉布拉多獵犬。據(jù)《科學(xué)警報》的米歇爾·斯塔爾報道，他們將狗的數(shù)據(jù)與320名1至103歲的人以及133只老鼠的甲基化特征進行了比較。

They found that people and dogs seem to age similarly when they are young, and then again in their older years.

他們發(fā)現(xiàn)，人與狗在年輕時似乎年齡相仿，在年老時又似乎相似。

The alignment of epigenetic clocks helped the researchers create a formula to calculate dog age in human years: human_age = 16ln(dog_age) + 31.

表觀遺傳時鐘的排列幫助研究人員創(chuàng)建了一個公式來計算狗的年齡:human_age = 16ln(dog_age) + 31。

The "ln" is an abbreviation for the natural logarithm of your dog's age in years, which you can calculate here.

ln是你的狗的年齡的自然對數(shù)的縮寫，你可以在這里計算。

So, multiply the natural logarithm of your dog's age in years by 16, then add 31. That's your dog's age in human years.

所以，把你的狗的自然對數(shù)乘以16，然后加上31。這是你的狗的年齡。

Using the formula, average life spans matched up for humans and Labs. (Photo: 4 PM production/Shutterstock)

There are times when dogs and people seem to follow the same aging trajectories. A 7-week-old puppy, for example, is closely aligned to a 9-month-old human baby, both of whom are just starting to have teeth. And the formula showed that average life spans match up for Labs (12 years) and humans (70 years).

有時候，狗和人似乎遵循著同樣的衰老軌跡。例如，一只7周大的幼犬與一個9個月大的人類嬰兒緊密相連，而這兩個嬰兒都剛剛開始長牙。該公式顯示，狗狗(12歲)和人類(70歲)的平均壽命相當(dāng)。

It's the adolescence and middle-age part that doesn't quite sync up. According to calculations, a 2-year-old dog is the equivalent of a 42-year-old person and a 5-year-old dog is nearly 57 in people years.

青春期和中年并不同步。根據(jù)計算，一只2歲的狗相當(dāng)于一個42歲的人，一只5歲的狗接近57歲的人。

Maybe you could just forget the math completely. After all, your dog is only as old as he feels.

其實你可以完全忘記數(shù)學(xué)。畢竟，你的狗只有它自己感覺的年齡。