Dec. 12 (UPI) -- Researchers in Australia have developed a new genetic analysis method capable of predicting the lifespan of vertebrate species.
The so-called "lifespan clock" -- described Thursday in the journal Scientific Reports -- relies on a survey of 42 genes associated with CpG sites. The densities of CpG sites, unique snippets of DNA, are associated with lifespan.
Measuring and comparing the maximum lifespan of different vertebrates species by tracking animals in the wild is difficult, but until now, scientists had yet to identify genetic markers for lifespan.
With the new research, scientists were able to identify several dozen genetic markers by studying the genomes of hundreds of vertebrates.
"The 42 genes were identified by firstly comparing the genomes, that is the full DNA sequence, of 252 vertebrate genomes compared to their known lifespans," lead study author Benjamin Mayne, a postdoctoral researcher at the University of Western Australia's Indian Oceans Marine Research Center, told UPI. "Using a regression model, we narrowed down 42 genes which, given the CpG density significantly correlated with increasing lifespan."
Researchers used the African elephant and its well-documented average lifespan of 65 years to calibrate the clock, allowing scientists to estimate the lifespan of the woolly mammoth and the straight-tusked elephant at 60 years.
With the genomes and lifespans of modern and early humans and chimpanzees as a reference, scientists determined the lifespans of Denisovans and Neanderthals were approximately 38 years.
"The model performed the best on mammals," Mayne said. "This may reflect a technical aspect of the project as human promoters were used to identify the 42 genes and hence may have bias toward the mammals. In the future we hope to make more precise models for different vertebrate classes."
Researchers were able use their clock to accurately predict the lifespans of especially long-living mammals, like the Pinta Island Tortoise and the bowhead whale. The clock determined the tortoise's maximum lifespan is 120 years. The bowhead whale can live up to 268 years, according to the clock.
"Lifespan is an important parameter in wildlife management," Mayne said. "Lifespan can be used to assist in determining the risk of animal extinction and for managing invasive species. In addition, it can also be used to determine the catch limits in fisheries."