Chinese scientists have discovered the genome sequence of snailfish, a typical deep-sea species from the Mariana Trench, the deepest part of the ocean.

Experts said the research was a breakthrough in the study of deep-sea creatures in understanding how  they adapt to hostile environments with dark, cold and extreme pressure.

The research team from the Institute of Deep-sea Science and Engineering and the Institute of Hydrobiology under the Chinese Academy of Sciences sampled the hadal snailfish (Pseudoliparis swirei) at a depth of 7,884 meters during an expedition to the Mariana Trench in the western Pacific Ocean two years ago.

The research result was published Monday on the journal, Nature Ecology and Evolution.

Snailfish can bear with the high pressure in the Mariana Trench, which was described by the Nature magazine as "similar to what someone would feel if the entire weight of the Eiffel Tower rested on their big toe."

The genome sequencing of the hadal snailfish shows that a gene for hardening bones is inactive, which indicates the skeleton made of cartilage is more pressure-tolerant.

They also found that hadal snailfish have lost several genes involved in sensing light, but five such genes are still active. Scientists believe that the fish might have retained some sight ability. (CGTN)