Precise formula for animal experiment design to calculate dog age

动物实验

z-bo

2020-07-22

846

How many years has your pet dog been with you? According to the famous "dog's age rule", a dog's year is equal to a person's seven years. A study published in "Cell Systems" (CellPress Cell Press) on July 2 shows that this statement is wrong. The age of dogs is much older than we thought. Researchers have devised a more precise formula through animal experiments that can calculate the age of dogs based on the chemical changes in DNA during biological aging.

　　 Dogs and their owners live in the same environment and receive almost the same medical care as humans. This provides scientists with a unique opportunity to study the aging of different species. Like humans, dogs have a similar developmental trajectory, and over time, dogs will get older and more likely to develop age-related diseases. However, aging at the molecular level is more complicated. It first ages rapidly and then slows down.

"In terms of the physical maturity of a one-year-old dog, a nine-month-old dog can give birth to a puppy. When you do the calculations, you will quickly find that it is more than just multiplying by 7." Trey Ideker of the University of California, San Diego, said: "It's like a 30-year-old man, how old is this one-year-old dog."

　　 There are no major changes in the lives of humans and dogs (who we are), but the chemical markers (called methylation markers) on the DNA have indeed changed. Adek thinks these marks are like wrinkles in the genome. "It is easy to think that it is similar to looking at a person's face and inferring age based on wrinkles, gray hair and other characteristics. These are just similar characteristics at the molecular level." Two researchers, with the help of dog experts, pulled 104 animals The Brad Retriever was investigated, ranging from puppies a few weeks ago to 16-year-old dogs. The two dog experts are Danika Bannasch of the University of California, Davis and Elaine Ostrander of the National Institutes of Health. They compared the changes in the methylation status of dogs and humans.

In order to better compare the life stages of dogs and humans, I found a new formula through comparison: human age = 16ln (dog’s age) + 31. According to this formula, all 8-week-old dogs in infancy are approximately equal to 9 month old baby. The average lifespan of a Labrador is 12 years, which is equivalent to 70 years of life for humans in the world.

　　" According to my new formula, Adek said: "I like keeping dogs, but I sympathize with this 6-year-old dog. I noticed that it is almost equivalent. In these two species, we found that age-based methylation mainly occurs in developmental genes and is activated before birth to create a body plan and regulate child development. Edek said that when a person stops growing as an adult, “most of these genes have been turned off, but they are still smoking.” “If you look at the methylation markers of these genes, they are still changing. "

　　 Based on these "smoking" genes, the research team can measure the age and physiological status of different species. However, other quantitative methylation age prediction methods can only be used for one species. Good results in China. Adek also pointed out that future surveys of different breeds of dogs with different life spans may give a better understanding of this new watch. It can be used not only as a tool to understand heterogeneous aging, but also in a clinical environment where veterinarians take active measures to treat animals.