Endangered Chinese Alligator Genome Sequenced By Researchers

The endangered Chinese alligator genome has been fully mapped by scientists from Zhejiang University and BGI Shenzhen.

There are currently less than 10,000 captive Chinese alligators and an estimated 100 in the wild. The alligators are mostly spread throughout the Zhejiang and Anhui Provinces of China.

The accomplishment marks the first time researchers have fully mapped a crocodilian genome.

The Chinese alligator is of special interest to researchers because of its ability to thrive in both aquatic and terrestrial habitats.

Researchers published their findings in Cell Research along with a plausible explanation of how terrestrial reptiles adapt to aquatic environments and temperature-dependent sex determination (TSD).

The genome was completed after scientists collected a sample from an endangered Chinese alligator from Changxing Yinjiabian Chinese Alligator Nature Reserve in Zhejiang Province, China.

Researchers used a whole-genome shotgun strategy by sequencing randomly-derived subsegments whose order and orientation within the whole are unknown until the final assembly of overlapping sequences is completed.

The shutgun approached yielded a sequence size of 2.3GB alongside 22,000 genes.

Researchers say the genome shows strong evidence that explains how the Chinese alligator is able to hold its breath underwater for long periods of time. Among the genomes discoveries is the inclusion of a duplicate bicarbonate-binding hemoglobin gene, positively selected energy metabolism, and more.

The full Chinese alligator genome also demonstrates genetic signatures of the powerful sensory system and immune system of the Chinese alligator.

The study also examines the Chinese alligators TSD and lack of sex chromosomes. TSD means the sex of the Chinese alligator is determined by incubation temperature at a specific point in the embryonic development.

The Chinese alligator is the first TSD based animal to have its full genome sequenced.

Scientists will now use the Chinese alligators genome to help better understand how animals adapt to aquatic and terrestrial life.