Bataillon T, Kirkpatrick M
INRA-SGAP, Domaine de Melgueil, Mauguio, France.
Genet Res. 2000 Feb;75(1):75-81. doi: 10.1017/s0016672399004048.
We studied the effects of population size on the inbreeding depression and genetic load caused by deleterious mutations at a single locus. Analysis shows how the inbreeding depression decreases as population size becomes smaller and/or the rate of inbreeding increases. This pattern contrasts with that for the load, which increases as population size becomes smaller but decreases as inbreeding rate goes up. The depression and load both approach asymptotic limits when the population size becomes very large or very small. Numerical results show that the transition between the small and the large population regimes is quite rapid, and occurs largely over a range of population sizes that vary by a factor of 10. The effects of drift on inbreeding depression may bias some estimates of the genomic rate of deleterious mutation. These effects could also be important in the evolution of breeding systems in hermaphroditic organisms and in the conservation of endangered populations.
我们研究了种群大小对由单个基因座上的有害突变引起的近亲繁殖衰退和遗传负荷的影响。分析表明，随着种群大小变小和/或近亲繁殖率增加，近亲繁殖衰退如何降低。这种模式与遗传负荷的模式形成对比，遗传负荷随着种群大小变小而增加，但随着近亲繁殖率上升而降低。当种群大小变得非常大或非常小时，衰退和负荷都接近渐近极限。数值结果表明，小种群和大种群状态之间的转变相当迅速，并且主要发生在种群大小相差一个数量级的范围内。遗传漂变对近亲繁殖衰退的影响可能会使一些有害突变基因组率的估计产生偏差。这些影响在雌雄同体生物繁殖系统的进化以及濒危种群的保护中也可能很重要。
