Genomic analysis reveals depression due to both individual and maternal inbreeding in a free-living mammal population.
Genomic analysis reveals depression due to both individual and maternal inbreeding in a free-living mammal population.
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DOI：
10.1111/mec.13681
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发表时间：
2016-07
影响因子：
4.9
通讯作者：
Pemberton JM
中科院分区：
文献类型：
--
作者：
Bérénos C;Ellis PA;Pilkington JG;Pemberton JM
有充分的证据表明近交衰退表现为焦点个体的健康或健康相关特征的减少。在许多生物体中，健康不仅受到个体携带的基因的影响，还受到父母携带的基因的影响，例如接受父母照顾的情况。虽然许多系统都描述了母体效应，但近亲繁殖直接通过焦点个体或间接通过其父母的近亲繁殖系数影响适应性的程度很少被联合研究。索伊绵羊研究群体是一个很好的系统，可以测试这两种影响，因为羔羊得到了长期的母性护理。在这里，我们使用谱系衍生的近交或使用约 37,000 个 SNP 标记计算的基因组估计器，测试了三个与健康相关的性状（出生体重、体重和 4 月龄时的后腿长度）和三个健康组成部分（第一年生存率、成年年生存率和年度繁殖成功率）的母体和个体近交抑郁。我们发现了近亲繁殖在 4 个月后腿和体重、雄性第一年存活率以及成年存活率和繁殖成功率方面的下降的证据。研究发现，母亲近亲繁殖会降低出生体重和 4 个月体重。我们使用基因组估计器发现了比谱系更多的显着近亲繁殖抑制的实例，这在一定程度上是通过可用样本量的增加来解释的。总之，我们的结果强调，跨代近交效应值得在有亲本照顾的物种中进行进一步探索，并且现代基因组工具可以成功地代替自然种群中的谱系，或与谱系一起使用。
There is ample evidence for inbreeding depression manifested as a reduction in fitness or fitness‐related traits in the focal individual. In many organisms, fitness is not only affected by genes carried by the individual, but also by genes carried by their parents, for example if receiving parental care. While maternal effects have been described in many systems, the extent to which inbreeding affects fitness directly through the focal individual, or indirectly through the inbreeding coefficients of its parents, has rarely been examined jointly. The Soay sheep study population is an excellent system in which to test for both effects, as lambs receive extended maternal care. Here, we tested for both maternal and individual inbreeding depression in three fitness‐related traits (birthweight and weight and hindleg length at 4 months of age) and three fitness components (first‐year survival, adult annual survival and annual breeding success), using either pedigree‐derived inbreeding or genomic estimators calculated using ~37 000 SNP markers. We found evidence for inbreeding depression in 4‐month hindleg and weight, first‐year survival in males, and annual survival and breeding success in adults. Maternal inbreeding was found to depress both birthweight and 4‐month weight. We detected more instances of significant inbreeding depression using genomic estimators than the pedigree, which is partly explained through the increased sample sizes available. In conclusion, our results highlight that cross‐generational inbreeding effects warrant further exploration in species with parental care and that modern genomic tools can be used successfully instead of, or alongside, pedigrees in natural populations.