Lines of mice selected for reproductive longevity

Area of Science:

• Gerontology
• Animal Genetics
• Reproductive Biology

Background:

• Understanding the genetic basis of longevity is crucial for aging research.
• Selective breeding offers a powerful tool to investigate genetic correlations between traits like reproduction and lifespan.

Purpose of the Study:

• To investigate the effects of selective breeding for reproductive longevity on lifetime reproductive performance and overall lifespan in mice.
• To determine the genetic and phenotypic correlations between reproductive longevity and lifespan.

Main Methods:

• Comparison of two mouse lines selected for reproductive longevity against an unselected control line.
• Monitoring of reproductive parameters (parturitions, litter size, offspring) and lifespan over multiple generations.
• Analysis of phenotypic and genetic correlations between reproductive longevity and lifespan.

Main Results:

• Selected mouse lines exhibited significantly increased lifetime parturitions (80-93% higher) and total offspring compared to the control line.
• While mean litter size was similar, reproductive persistency was markedly improved in selected lines.
• Lifespan was 17% longer in selected lines compared to the control line, with a phenotypic correlation of ~0.75 and genetic correlation of ~0.25 between reproductive longevity and lifespan.

Conclusions:

• Selective breeding is effective in improving reproductive longevity in mice.
• Increased reproductive longevity can lead to a correlated increase in overall lifespan.
• These selectively bred mouse lines provide a valuable model for studying aging and longevity.