Genomics can be used in many of ways to improve the conservation of the Black-footed Ferret.
Black-footed Ferret breeding has been intensely managed using theoretical measures of genetic diversity based on kinship. But because all living ferrets share the same ancestry at a kinship level between first cousins and siblings, it very difficult to choose mate pairs. Genome sequencing can create an empirical decision matrix that will allow breeders to selecting mate-pairs based on the unique genetic contribution their offspring will receive, rather than on kinship. Whole genome analyses can identify maladaptive genes responsible for traits associated with inbreeding depression, such as low sperm mobility, cryptorchidism, and kinked tails, and prevent the accumulation of these traits in the population. Studying genomes of wild-born ferrets can help identify what alleles are selected in the wild in order to breed ferrets in captivity more suited to their particular release sites.
In order to maximize the benefits of genomic technologies in the recovery of ferrets requires building a databank of genomic knowledge, which Revive & Restore initiated in 2014.
In 2014, in partnership with San Diego Zoo Global’s (SDZG) Frozen Zoo and Cofactor Genomics, Revive & Restore sequenced the genomes of four, carefully selected Black-footed Ferret samples to assess some preliminary questions about the species’ history and its conservation:
- How diverse was the last wild population of ferrets that founded the captive breeding program?
- Has overall genomic diversity decreased over the past 30 years?
- Does integrating historic individuals restore genomic diversity?
- How much diversity might be gained with continued genetic rescue efforts?
The study individuals include two unique individuals captured at Meeteetse, Wyoming in the 1980s, a living ferret born in 2009 whose genetics is representative of the current captive population, a unique individual born in 2010 as the result of artificial insemination using semen cryopreserved in the 1980s. (This was an early genetic rescue attempt to restore lost diversity.) The DNA samples of two living ferrets born in captivity were provided by the Black-footed Ferret Recovery Team, while the Frozen Zoo provided the historic samples for the two individuals born in the wild. Both these ferrets were members of the population that founded the captive breeding program, so their genomes represent a sample of the genetic diversity of the founding generation of all living ferrets. However, these ferrets’ unique genetic lineages were lost completely during the captive breeding program. Therefore, their cryopreserved cells are a resource for cloning, for restoring lost genetic diversity, and for infusing new genetic variation.