Long Lived Lonesome George Clues to Longevity

Charles Darwin developed the idea of natural selection using the tortoises he found on the Galapagos island back in 1835. He preached the idea that these amazing animals adapted there shell to help them survive the lifestyle they endured. In 2012, Lonesome George- the longest living original turtle from the islands- passed away. However he was still giving hints to scientists about longevity and good health. Dr. Aldagisa Caccone,  sequenced the entire genome of Lonesome George and then compared it to other genomes of living animals. She found that there was a gene mutation, IGF1R, that is also found in humans that could be key to longevity in the turtle AND humans.  This gene has one copy in the human genome however the tortoise carried 12. This makes it much more effeceint to carry out these processes to help the turtle live a century.

The amazing part about these tortoises is that they offer so much information to humans. If we can study them more and learn about there genome, we could have solutions to regeneration of body parts. They could survive temperatures that humans could not possible survive. And much like in 1835, were the tortoises were helping the world understand evolution, Lonesome George is once again teaching the world about adaptation and longevity.

Is There a Fountain of Youth Gene?

Giant tortoises are known for their long life expectancies. Yet, when the only surviver of the Pinta Island Tortoises of the Galapagos named George, passed after a century it sent scientists on a longevity hunt. Researchers reported a discovery within George's genome relative to his long life span. These gene components were linked to a strong immune system, efficient DNA repair, and cancer resistance. Two scientists in particular, Dr. Adalgisa Caccone and Dr. Carlos Lopez-Otin, came together to dissect which parts of George's DNA were functional and what those functions may be. The scientists sequenced George's entire genome, as well as that of another Aldabra giant tortoise, then compared that genome with those of mammals, fish, birds, and other reptiles. Results suggested that a mutation in the gene IGF1R, which is associated with longevity in humans, could be the cause of a tortoises long life span. It was also discovered that tortoises contained several more copies of genes related to DNA repair, tumor suppression, and immunity. To be exact, a tortoises genome contained twelve copies of the gene PRF1, involved with immune response, compared to humans who only contain one. So, is this the fountain of youth? Are gene mutations the components to a living a long life? Further research and many lessons are to be learned from our closest relatives, the reptiles.

Lonesome George of the Galapagos 

As a person working in the medical field, i found this article really valuable. It has been discovered that reptiles are capable of regenerating entire body parts. This could be extremely beneficial to the medical community. I hope further research in genome sequencing can lead to better treatments for patients all over the world.

New Species of Galápagos Tortoise: Chelonoidis donfaustoi

 

 

Last month scientist discovered a new species of Galapagos tortoise. These are the giants that helped inspire Darwin’s theory of evolution. This new species of Galapagos tortoise lives in eastern Santa Cruz, also known as Cerro Fatal or Deadly Hill, due to its arid and lava-laced environment. This is confirmed as the 14^th Galapagos tortoise. The new species goes by the name, Chelonoisis donfaustoi, after Fausto Llerena Sanchez who just retired after forty-three years of helping to save the endangered tortoises.

The species evidently has more in common genetically with species of tortoise on other islands and less in common with Santa Cruz’s main tortoise. Although it is not common for separate species to breed with each other, the genetic evidence shows that the two Santa Cruz species have mated. The genetic analysis that compared Cerro Fatal DNA with DNA from all known species showed that the Reserva specimen contained traces of Cerro Fatal DNA, which indicated that the two species can actually interbreed but have a tendency not to. Cerro Fatal has about two-hundred and fifty tortoises, while La Reserva, a moister and elevated part of Santa Cruz has about two-thousand tortoises. Reserva tortoises have been in existence for one and three-quarter million years, unlike the Cerro Fatal tortoises which have only existed for less than half a million years.

Although the two tortoise types shared an island, genetic analysis revealed that the closest relatives the two species have in common are from San Cristolbal which is the most eastern Galapagos island. This analysis also revealed that they are not each other’s sister species and that the Cerro Fatal tortoises evolved much more recently. Tortoise expert, Peter Paul van Dijk stated that the “results suggest that Cerro Fatal tortoise probably drifted to Santa Cruz during a once-in-a-decade or once-in-a-century extreme weather event.”

This discovery gives scientists hope that the new species designation will allow them to raise money to further study Cerro Fatal tortoises and more importantly to better protect their habitat and surroundings.

Original Article