Whole-genome sequencing uncovers the mysteries of the endangered Chinese alligator

August 9, 2013

In a study published in Cell Research, Chinese scientists from Zhejiang University and BGI have completed the genome sequencing and analysis of the endangered Chinese alligator (Alligator sinensis). This is the first published crocodilian genome, providing a good explanation of how terrestrial-style reptiles adapt to aquatic environments and temperature-dependent sex determination (TSD).

The Chinese alligator is a member of the alligator family that lives in China. It is critically endangered with a population of ~100 wild and ~10,000 captive individuals in Zhejiang and Anhui Provinces. Great efforts have been put into uncovering the mysteries of this species because of its unique features that allow them being adapted for living in both water and land habitats.

In this study, researchers collected a Chinese alligator sample from Changxing Yinjiabian Chinese Alligator Nature Reserve (Zhejiang Province, China) and sequenced its genome using a whole-genome shotgun strategy. The genomic data yielded a of Chinese alligator with the size of 2.3 Gb, and a total of 22,200 genes were predicted.

The provides a strong evidence from DNA level to illustrate why Chinese alligator can hold its breath under water for long periods of time, such as the duplication of the bicarbonate-binding hemoglobin gene, positively selected , and others. Researchers further identified the genetic signatures of the powerful sensory system and immune system of Chinese alligator. All the results presented evidence for co-evolution of multiple systems specific to the back-to-the water transition.

Chinese alligator exhibits TSD, and does not possess sex chromosomes. The absence of sex chromosomes is another interesting feature. In this study, researchers analyzed the of , and reported that the alligator was the first TSD species whose genome has been sequenced, which will have great implication in resolving sex .

Shengkai Pan, Project manager from BGI, said, "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."

Explore further: Reintroduced Chinese alligators now multiplying in the wild in China

Related Stories

Alligator fat could be used to make biodiesel

August 18, 2011

(PhysOrg.com) -- In addition to being a novelty food, alligators could also provide a feedstock for biodiesel. Every year, the alligator meat industry disposes of about 15 million pounds of alligator fat in landfills. Now ...

Rare albino alligator goes on show in US

October 7, 2011

An extremely rare albino alligator from the swamps of Louisiana is taking up residence in Washington, dazzling visitors with her brilliant white skin.

Recommended for you

Most EU nations seek to bar GM crops

October 4, 2015

Nineteen of the 28 EU member states have applied to keep genetically modified crops out of all or part of their territory, the bloc's executive arm said Sunday, the deadline for opting out of new European legislation on GM ...

Ancestral background can be determined by fingerprints

September 28, 2015

A proof-of-concept study finds that it is possible to identify an individual's ancestral background based on his or her fingerprint characteristics – a discovery with significant applications for law enforcement and anthropological ...

Trade in invasive plants is blossoming

October 3, 2015

Every day, hundreds of different plant species—many of them listed as invasive—are traded online worldwide on auction platforms. This exacerbates the problem of uncontrollable biological invasions.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.