Genetic management on the brink of extinction: Sequencing microsatellites does not improve estimates of inbreeding in wild and captive Vancouver Island marmots (Marmota vancouverensis)
Date
2022-01-16Author
Barrett, Kimberley G.
Amaral, Geneviève
Elphinstone, Melanie
McAdie, Malcolm L.
Davis, Corey S.
Janes, Jasmine K.
Carnio, John
Moehrenschlager, Axel
Gorrell, Jamieson C.
Metadata
Show full item recordAbstract
Captive breeding is often a last resort management option in the conservation of endangered species which can in turn lead
to increased risk of inbreeding depression and loss of genetic diversity. Thus, recording breeding events via studbook for
the purpose of estimating relatedness, and facilitating mating pair selection to minimize inbreeding, is common practice.
However, as founder relatedness is often unknown, loss of genetic variation and inbreeding cannot be entirely avoided.
Molecular genotyping is slowly being adopted in captive breeding programs, however achieving sufficient resolution can be
challenging in small, low diversity, populations. Here, we evaluate the success of the Vancouver Island marmot (Marmota
vancouverensis; VIM; among the worlds most endangered mammals) captive breeding program in preventing inbreeding
and maintaining genetic diversity. We explored the use of high-throughput amplicon sequencing of microsatellite regions to
assay greater genetic variation in both captive and wild populations than traditional length-based fragment analysis. Contrary
to other studies, this method did not considerably increase diversity estimates, suggesting: (1) that the technique does not
universally improve resolution, and (2) VIM have exceedingly low diversity. Studbook estimates of pairwise relatedness and
inbreeding in the current population were weakly, but positively, correlated to molecular estimates. Thus, current studbooks
are moderately effective at predicting genetic similarity when founder relatedness is known. Finally, we found that captive
and wild populations did not differ in allelic frequencies, and conservation efforts to maintain diversity have been successful
with no significant decrease in diversity over the last three generations.
Identifier (Other)
DOI: 10.1007/s10592-022-01429-7DOI: 10.25316/IR-17075