A team of Chinese scientists has successfully sequenced and analyzed the genome of Rangifer tarandus (reindeer), the only fully domesticated species in the deer family Cervidae.
The reindeer (Rangifer tarandus).
Rangifer tarandus is native to arctic, subarctic, tundra, boreal, and mountainous regions of northern Europe, Siberia, and North America.
Reindeer is the European name for this species, while in North America the species is known as caribou.
Unlike all other cervids, female Rangifer tarandus regularly grow antlers (defining characteristics of cervids), as well as males.
Moreover, their milk contains more protein and less lactose than cow’s milk. The latter aspect makes the availability of this milk of interest given the high percentage of lactose intolerant people in the world.
“With this variety of unique features, the availability of a reindeer genome sequence can provide an entire sleigh-full of new information, and is a welcome new member to the elite club of domesticated species with reference genomes, including the cow, sheep and goat,” the researchers said.
The authors took a blood sample from a two-year-old, female reindeer of a domesticated herd maintained by nomadic Ewenki hunter-herders in the Greater Khingan Mountains in China.
They sequenced, assembled, annotated the genome and showed it was of high quality.
According to the team, the size of the reindeer genome is 2.6 GB (2.6 billion base pairs) — slightly smaller than that of humans, cows, and goats, and about the same size as sheep.
“We also identified 335 reindeer-specific genes that are likely to aid in understanding the special biological characteristics of reindeer,” said first author Dr. Zheping Li, from the Institute of Special Animal and Plant Sciences at the Chinese Academy of Agricultural Sciences.
“These could also be very useful in understanding the evolution of the reindeer as well as all Cervidae in future comparative genomics studies between reindeer and other ruminants.”
With this goal in mind, the scientists also constructed an evolutionary tree using the new genome and the already available genomes of members of the bovine family.
They found that reindeer, cattle, and goats separated from a common ancestor approximately 29.6 million years ago.
“This was during the Oligocene epoch, when one of the major changes was the global expansion in grasslands,” the researchers said.
The research was just published in the journal GigaScience.
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Zhipeng Li et al. Draft genome of the Reindeer (Rangifer tarandus). GigaScience, published online November 1, 2017; doi: 10.1093/gigascience/gix102
