Latest Dog to Human Aging Formula
This month researchers published the results of new research into this age-old question in the preprint repository bioRxiv. This new research looked at common epigenetic changes in 104 Labradors spanning a 16 year age range. An epigenetic change is a chemical change in gene expression which affects how the cells read the genes. In simplest of terms, scientists have discovered that the aging process is reflected by DNA methylation – the addition of methyl groups to the DNA molecule.
The rate these methyl groups are added is dependant on our DNA, and also the stresses and toll of disease and poor lifestyle habits. This forms a biological clock known as the epigenetic clock which can be used to calculate an age estimate and even a prediction of life expectancy!
The researchers decided to look at a single breed, Labrador Retrievers, and scan DNA methylation patterns. Results showed similar age-related methylation to that of humans, particularly evident in the young and old ends of the spectrum.
The researchers matched up the rate of methylation changes in dogs with that of the human epigenetic clock to create a new dog age conversion formula. This formula applies to dogs older than 1, calculates that a dog’s human age roughly equals the natural logarithm of the dog's age, multiplied by 16, plus 31 (16 ln(dog age) + 31).
The formula generates a VERY non-linear relationship between dog age and human age. Based on epigenetic clocks, dogs age extremely quickly in their first few years, but then this aging slows down dramatically.