Breakthrough genetic discovery on Saola
Saola carries high genetic load due to long genomic regions lacking diversity - a characteristic of endangered species.
Saola is one of the rarest and most mysterious species in the world.
The saola (Pseudoryx nghetinhensis) is a hoofed mammal endemic to the Annamite Mountains. Since its discovery, the saola has remained one of the world's most enigmatic mammals due to its small population size and extreme difficulty in observing it in the wild.
To better understand this rare animal, a group of international and Vietnamese scientists, including Associate Professor Dr. Le Duc Minh from the Faculty of Environment, University of Science (Vietnam National University, Hanoi) conducted a full genome sequencing and for the first time identified important genetic characteristics of this animal.
The study was conducted on 26 bone and soft tissue samples collected and preserved over the past 30 years. Genetic analysis results showed that the saola is an ancient animal, distantly related to cattle, Associate Professor Dr. Le Duc Minh shared on the news of Hanoi National University.
Despite its small distribution range, the saola has a genetic split into two main populations: one in the North (Ha Tinh - Quang Binh) and one in the South (Hue - Quang Nam). This split is estimated to have occurred about 5,000-20,000 years ago, coinciding with the last ice age.
One notable point is that saola carries a high genetic load due to long genome regions lacking diversity - a characteristic of endangered species.
However, the deleterious variants were mainly concentrated in non-coding regions, and were not shared between the two populations, suggesting that the species' resistance and recessive deleterious gene elimination mechanisms still exist.
The research results are presented in the article “Genomes of critically endangered saola are shaped by population structure and purging” in the journal Cell.