Conservation Genetics

, Volume 6, Issue 5, pp 655–663 | Cite as

Methods for minimizing the loss of genetic diversity in conserved populations with overlapping generations

  • Tetsuro Nomura


Minimization of the average coancestry in a population has been theoretically proven to be the most efficient method to preserve genetic diversity. In the present study, based on a population genetic model, two methods to minimize the average coancestry in populations with overlapping generations were developed. For a given parental coancestry structure, the first method (OG) minimizes the average coancestry in the next generation, and the second method (LT) is designed to minimize the long-term accumulation of coancestry. The efficiencies of the two methods were examined by stochastic simulation. Compared to random choice of parents, the annual effective population sizes under the two proposed methods increased 2–3 folds. The difference among the two methods was small in a population with short generation interval. For populations with long generation intervals, the OG method showed a slightly larger annual effective size in an initial few years. However, in the subsequent years, the LT method gave a 5–15% larger annual effective size than the OG method. From these results, it is suggested that the LT method would be preferred to the OG method in most practical situations.

Key words:

coancestry effective population size genetic diversity overlapping generations 


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I am grateful to Richard Frankham and two anonymous referees for helpful comments and suggestions. This work was supported in part by the Grants-in-Aid for scientific research (No. 14560241 and 15658076) from the Ministry of Education, Culture, Sports, Science and Technology of Japan.


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Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  1. 1.Department of Biotechnology, Faculty of EngineeringKyoto Sangyo UniversityKyotoJapan

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