Pariset Lorraine, Joost Stephane, Marsan Paolo Ajmone, Valentini Alessio
Dipartimento di Produzioni Animali, Università della Tuscia, Viterbo, Italy.
BMC Genet. 2009 Feb 19;10:7. doi: 10.1186/1471-2156-10-7.
In this study we compare outlier loci detected using a FST based method with those identified by a recently described method based on spatial analysis (SAM). We tested a panel of single nucleotide polymorphisms (SNPs) previously genotyped in individuals of goat breeds of southern areas of the Mediterranean basin (Italy, Greece and Albania). We evaluate how the SAM method performs with SNPs, which are increasingly employed due to their high number, low cost and easy of scoring.
The combined use of the two outlier detection approaches, never tested before using SNP polymorphisms, resulted in the identification of the same three loci involved in milk and meat quality data by using the two methods, while the FST based method identified 3 more loci as under selection sweep in the breeds examined.
Data appear congruent by using the two methods for FST values exceeding the 99% confidence limits. The methods of FST and SAM can independently detect signatures of selection and therefore can reduce the probability of finding false positives if employed together. The outlier loci identified in this study could indicate adaptive variation in the analysed species, characterized by a large range of climatic conditions in the rearing areas and by a history of intense trade, that implies plasticity in adapting to new environments.
在本研究中,我们将使用基于FST的方法检测到的异常位点与最近描述的基于空间分析(SAM)的方法所识别的位点进行比较。我们测试了一组先前在意大利、希腊和阿尔巴尼亚等地中海盆地南部地区山羊品种个体中进行基因分型的单核苷酸多态性(SNP)。我们评估了SAM方法在SNP方面的表现,由于SNP数量众多、成本低且易于评分,它们正越来越多地被采用。
这两种异常检测方法的联合使用(以前从未使用SNP多态性进行过测试),通过这两种方法鉴定出参与牛奶和肉质数据的相同三个位点,而基于FST的方法在检测的品种中还识别出另外3个处于选择扫荡下的位点。
对于FST值超过99%置信限的情况,使用这两种方法得到的数据似乎是一致的。FST和SAM方法可以独立检测选择特征,因此如果一起使用,可以降低发现假阳性的概率。本研究中鉴定出的异常位点可能表明所分析物种的适应性变异,其特点是饲养地区气候条件范围广泛且有强烈的贸易历史,这意味着在适应新环境方面具有可塑性。