A team of researchers have completed the genome sequencing and analysis of the endangered Chinese alligator, making it the first published crocodilian genome and offering a new look into how the land-based reptile has come to adapt to its watery environment over time.
Published in the journal Cell Research, the study was conducted by scientists from Zhejiang University and BGI who collected a Chinese alligator sample from Changxing Yinjiabian Chinese Alligator Nature Reserve in Zhejiang Province, China.
The resulting genomic data offers DNA-level evidence as to why the creature can hold its breath under water for an extended period of time, including the duplication of the bicarbonate-binding hemoglobin gene and positively selected energy metabolism, among other things.
The scientists were also able to identify the genetic signatures of the alligator's powerful sensory and immune system.
Combined, the data the team collected all points toward a "co-evolution of multiple systems specific to the back-to-the-water transition," according to a press release on the study.
Furthermore, as the Chinese alligator exhibits temperature-dependent sex determination (TSD), the study marks the first sequencing of a TSD species' genome, which, the scientists argue, "will have great implication in resolving sex chromosome evolution."
With just 100 or so left in the wild and 10,000 in captivity, the Chinese alligator ranks as one of the world's critically endangered species. For this reason, scientists are eager to understand its unique ability to live in both water and land habitats as well as increase their ability to save it from extinction.
"The accomplishment of the Chinese alligator genome is significant for understanding its adaptation for both aquatic and terrestrial environments, and more importantly, for the conservation of such an endangered species," Shengkai Pan, Project manager from BGI, said.