In the search for novel genetic diversity that affects the timing of life history traits, we investigated a wild-derived stock of mice (Pohn). Early generations showed extended reproductive life span; however, this phenotype diminished with propagation of the stock. Out-crossing latter generation Pohn mice to C57BL/6J (B6) mice produced PohnB6F1 hybrids with remarkably extended reproductive life spans - mean age at last litter of 647 ± 32 days - longer than for the parental strains (70% longer than Pohn, 88% longer than B6) and longer than for highly heterogeneous crosses of laboratory mice. Litter size among young PohnB6F1 adults was similar to parental stocks, but their age-related decline in litter size was delayed by 150-200 days, resembling the earlier Pohn generations. Possibly, out-crossing Pohn mice unmasked cryptic alleles that promote extended female reproduction. This work establishes the PohnB6F1 hybrid as a new model for delayed reproductive aging.
|Original language||English (US)|
|Number of pages||12|
|Journal||Journals of Gerontology - Series A Biological Sciences and Medical Sciences|
|State||Published - Nov 2007|
Bibliographical noteFunding Information:
ACKNOWLEDGMENTS This work was supported by grants RR-14455, AG-025007, and AG025707 (DEH); Maine Biomed Res Infrastructure/NCRR/2 P20 RR016463 and The Goldwater Fellowship Foundation (YB); and The Jackson Laboratory cancer core grant HL63230.