Biology Faculty Articles
Document Type
Article
Publication Date
2-28-2023
Publication Title
Genes
Keywords
Pusa sibirica, conservation, pinnipeds, demography, heterozygosity
ISSN
2073-4425
Volume
14
Issue/No.
3
First Page
619
Abstract
Pusa sibirica, the Baikal seal, is the only extant, exclusively freshwater, pinniped species. The pending issue is, how and when they reached their current habitat—the rift lake Baikal, more than three thousand kilometers away from the Arctic Ocean. To explore the demographic history and genetic diversity of this species, we generated a de novo chromosome-length assembly, and compared it with three closely related marine pinniped species. Multiple whole genome alignment of the four species compared with their karyotypes showed high conservation of chromosomal features, except for three large inversions on chromosome VI. We found the mean heterozygosity of the studied Baikal seal individuals was relatively low (0.61 SNPs/kbp), but comparable to other analyzed pinniped samples. Demographic reconstruction of seals revealed differing trajectories, yet remarkable variations in Ne occurred during approximately the same time periods. The Baikal seal showed a significantly more severe decline relative to other species. This could be due to the difference in environmental conditions encountered by the earlier populations of Baikal seals, as ice sheets changed during glacial–interglacial cycles. We connect this period to the time of migration to Lake Baikal, which occurred ~3–0.3 Mya, after which the population stabilized, indicating balanced habitat conditions.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
NSUWorks Citation
Yakupova, Aliya; Andrey Tomarovsky; Azamat Totikov; Violetta R. Beklemisheva; Maria Logacheva; Polina Perelman; Aleksey Komissarov; Pavel Dobrynin; Ksenia Krasheninnikova; Gaik Tamazian; Natalya A. Serdyukova; Michael Rayko; Tatiana Bulyonkova; Nikolay Cherkasov; Vladimir Pylev; Vladimir Peterfeld; Aleksey Penin; Elena Balanovska; Alla L. Lapidus; DNA Zoo Consortium; Stephen James O'Brien; Alexander S. Graphodatsky; Klaus-Peter Koepfli; and Sergey Kliver. 2023. "Chromosome-Length Assembly of the Baikal Seal (Pusa sibirica) Genome Reveals a Historically Large Population Prior to Isolation in Lake Baikal." Genes 14, (3): 619. doi:10.3390/genes14030619.
ORCID ID
0000-0001-7353-8301
ResearcherID
N-1726-2015
DOI
10.3390/genes14030619
Comments
The work was supported by a research grant of the Russian Science Foundation (RSF, 19-14-00034-P) and partly by a research grant of the Russian Foundation for Basic Research (RFBR), project number 20-04-00808. A.L. and M.R. were supported by St. Petersburg State University (grant ID PURE: 73023672). N.C. and G.T. were supported by Peter the Great St. Petersburg Polytechnic University in the framework of Russian Federation’s Priority 2030 Strategic Academic Leadership Programme (Agreement 75-15-2021-1333). V.P. and E.B. were funded from the state assignment of Ministry of Science and Higher Education of the Russian Federation for Research Centre for Medical Genetics.