近交衰退:我们检测到了吗

Inbreeding depression: Have we observed them?

近交衰退产生的原因是近交增加了有害等位基因纯合几率,导致个体适应能力下降。种群变小是导致近交衰退的主要原因,但在实际研究中发现近交衰退并非一定明显表现出来,这可能有以下几个主要的原因遗传负荷的淘汰、在较好的环境下近交衰退会表现不明显、并非能在所有性状中检测到近交衰退、近交衰退只出现在某些发育阶段和不同家系、种群、个体中的近交衰退程度不同。这提示我们近交衰退与生态及遗传密切相关。

Inbreeding may reduce population fitness through the expression of recessive and deleterious alleles in homozygous form. Small populations are more vulnerable for inbreeding depression, but their responses to the depression may not be observed due to the genetic load purged in studied species, benign environment investigated, differences in studied traits, different development stages of studied species, and different family lines, populations, and individuals used. All of these imply that the levels of inbreeding depression are affected ecologically and genetically. The genetic bases of different traits are associated with different ecological factors, causing the expression of inbreeding depression differed in phenotypic traits.