一种用人类年龄计算狗狗年龄的新方法

一种用人类年龄计算狗狗年龄的新方法

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.

人们过去认为，要得到相当于狗的年龄(以人类的年龄计算)的大致数字，只需乘以7即可。但在这个等式背后真的没有任何科学依据。他们的理论是，狗活了大约10年，人活了大约70年，所以用乘、除计算。

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.

但研究人员根据犬类DNA随时间的变化，提出了一个新的公式，可以把狗的年龄换算成人的年龄。

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.”

加州大学圣地亚哥分校的遗传学家使用了一种叫做DNA甲基化的方法。随着动物年龄的增长，DNA会捕捉到称为甲基的原子链。根据史密森尼的研究，由于甲基化是随着年龄的增长而稳定发生的，研究人员可以用它来估计人类的年龄。这被称为“表观遗传钟”。

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.

在同行评审之前发表在bioRxiv预印本上的这篇新论文中，研究人员将人与狗的表观遗传时钟进行了比较。尽管不同品种的狗寿命差异很大，但它们仍然遵循着相似的发展轨迹。他们在10个月左右进入青春期，并在20岁之前死亡，科学杂志指出。

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.

为了便于研究，研究人员集中在一个品种上，研究了104只从4周到16岁的拉布拉多猎犬。据《科学警报》的米歇尔·斯塔尔报道，他们将狗的数据与320名1至103岁的人以及133只老鼠的甲基化特征进行了比较。

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

他们发现，人与狗在年轻时似乎年龄相仿，在年老时又似乎相似。

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

表观遗传时钟的排列帮助研究人员创建了一个公式来计算狗的年龄: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是你的狗的年龄的自然对数的缩写，你可以在这里计算。

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，把你的狗的自然对数乘以16，然后加上31。这是你的狗的年龄。

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).

有时候，狗和人似乎遵循着同样的衰老轨迹。例如，一只7周大的幼犬与一个9个月大的人类婴儿紧密相连，而这两个婴儿都刚刚开始长牙。该公式显示，狗狗(12岁)和人类(70岁)的平均寿命相当。

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。根据计算，一只2岁的狗相当于一个42岁的人，一只5岁的狗接近57岁的人。

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

其实你可以完全忘记数学。毕竟，你的狗只有它自己感觉的年龄。