Balestre M, Von Pinho R G, Souza J C, Lima J L
Departamento de Biologia, Universidade Federal de Lavras, Lavras, MG, Brasil.
Genet Mol Res. 2008 Aug 5;7(3):695-705. doi: 10.4238/vol7-3gmr458.
The present study compared different similarity and dissimilarity coefficients and their influence in maize inbred line clustering. Ninety maize S0:1 inbred lines were used and genotyped with 25 microsatellite markers (simple sequence repeat). The simple matching, Rogers and Tanimoto, Russel and Rao, Hamann, Jaccard, Sorensen-Dice, Ochiai, and Roger's modified distance coefficients were compared by consensus index, projection efficiency in a two-dimensional space and by Spearman's correlation. Changes were found in high genetic similarity groupings with different coefficients using the consensus index. Russel and Rao and Jaccard coefficients had the greatest stress values with 75.67 and 40.16%, respectively, indicating that these coefficients should not be used. Genotype ranking changed, mainly in the comparison of the Roger's modified distance in relation to some coefficients (rs = 0.75). Russel and Rao's and Jaccard's coefficients should be avoided for their low accuracy. Moreover, genotype clustering by different similarly coefficients, without a close consideration of these coefficients could affect the research results.
本研究比较了不同的相似性和相异性系数及其对玉米自交系聚类的影响。使用了90个玉米S0:1自交系，并利用25个微卫星标记（简单序列重复）进行基因分型。通过一致性指数、二维空间中的投影效率以及Spearman相关性，对简单匹配、罗杰斯和谷本、拉塞尔和饶、哈曼、杰卡德、索伦森-迪茨、 Ochiai以及罗杰斯修正距离系数进行了比较。使用一致性指数发现，不同系数在高遗传相似性分组中存在变化。拉塞尔和饶系数以及杰卡德系数的应力值最大，分别为75.67%和40.16%，表明不应使用这些系数。基因型排名发生了变化，主要体现在罗杰斯修正距离与某些系数的比较中（rs = 0.75）。由于拉塞尔和饶系数以及杰卡德系数准确性较低，应避免使用。此外，在未充分考虑这些系数的情况下，使用不同相似性系数进行基因型聚类可能会影响研究结果。
