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ABSTRACT Increased parental relatedness occurs in small wild populations and in closed colonies in captivity and reduces offspring fitness. A closed colony ofPeromyscus maniculatusis maintained as genetically diverse stock at the Peromyscus Genetic Stock Center since 1963. Breeding records are available for all the years of breeding in captivity, which allows evaluation of the breeding performance since the inception of the stock. Kinship calculations showed that increased parental relatedness results in offspring loss, which is consistent with the operation of inbreeding depression and is common in small populations, both wild and captive. Nonetheless, an adaptive response was recorded that mitigated the adverse consequences of inbreeding and contributed to the long‐term stability of the colony: When parental relatedness increased, more offspring were produced, resulting in the overall number of viable offspring being unaffected. The underlying mechanism involved adjustments in the interval for mating between related parents, causing the production of more litters. These adaptive changes indicate that the harmful consequences of inbreeding may be partially relieved by mechanisms involving changes in the animals' reproductive strategy. The availability of the breeding records ofP. maniculatusenables the performance of additional studies asking different questions regarding the breeding dynamics of a closed colony under regulated conditions.
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Genomic variation in captive deer mouse (Peromyscus maniculatus) populations
Abstract Background Deer mice (genus Peromyscus ) are the most common rodents in North America. Despite the availability of reference genomes for some species, a comprehensive database of polymorphisms, especially in those maintained as living stocks and distributed to academic investigators, is missing. In the present study we surveyed two populations of P. maniculatus that are maintained at the Peromyscus Genetic Stock Center (PGSC) for polymorphisms across their 2.5 × 10 9 bp genome. Results High density of variation was identified, corresponding to one SNP every 55 bp for the high altitude stock (SM2) or 207 bp for the low altitude stock (BW) using snpEff (v4.3). Indels were detected every 1157 bp for BW or 311 bp for SM2. The average Watterson estimator for the BW and SM2 populations is 248813.70388 and 869071.7671 respectively. Some differences in the distribution of missense, nonsense and silent mutations were identified between the stocks, as well as polymorphisms in genes associated with inflammation (NFATC2), hypoxia (HIF1a) and cholesterol metabolism (INSIG1) and may possess value in modeling pathology. Conclusions This genomic resource, in combination with the availability of P. maniculatus from the PGSC, is expected to promote genetic and genomic studies with this animal model.
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- Award ID(s):
- 1736150
- PAR ID:
- 10300120
- Date Published:
- Journal Name:
- BMC Genomics
- Volume:
- 22
- Issue:
- 1
- ISSN:
- 1471-2164
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1186/s12864-021-07956-w
