The analysis also found specific alterations in two genes whose overexpression is known to contribute to cancer, and which may be part of a giant-tortoise-specific cancer mechanism. The researchers have found that tumor suppressors are expanded in the tortoises’ genomes compared to other vertebrates.

These genes may explain the generous size and long lifespans of these species. When researchers compared Lonesome George’s genome, as well as that of the Aldabra giant tortoise ( Aldabrachelys gigantea), to other species, they found genes associated with metabolism regulation and immune response. Back then, Yale University and Universidad de Oviedo, Spain, sequenced the genome of the famous Lonesome George, who died in 2012 at age of 100 and was the last giant tortoise on Pinta Island. The new study builds upon past research performed in 2018. These extra copies are thought to offer protection against the biological degeneration typically associated with aging, including cancer. How do they do it? In a new study, researchers at the University of Buffalo compared the genomes of Galápagos giant tortoises with those of other turtles and found the animals evolved to have extra copies of certain genes. One captive individual, Harriet, lived for at least 175 years. Galápagos giant tortoises are one of the longest-lived vertebrates, with many living past 100 years of age in the wild. Galápagos tortoises. Credit: Ylenia Chiari.

Pinta tortoises