Ravel Catherine, Praud Sébastien, Murigneux Alain, Canaguier Aurélie, Sapet Frédéric, Samson Delphine, Balfourier François, Dufour Philippe, Chalhoub Boulos, Brunel Dominique, Beckert Michel, Charmet Gilles
INRA, UMR1095, Amélioration et Santé des Plantes, 234 avenue du Bézet, Clermont-Ferrand, F-63100 France.
Genome. 2006 Sep;49(9):1131-9. doi: 10.1139/g06-067.
Information on single-nucleotide polymorphisms (SNPs) in hexaploid bread wheat is still scarce. The goal of this study was to detect SNPs in wheat and examine their frequency. Twenty-six bread wheat lines from different origins worldwide were used. Specific PCR-products were obtained from 21 genes and directly sequenced. SNPs were discovered from the alignment of these sequences. The overall sequence polymorphism observed in this sample appears to be low; 64 single-base polymorphisms were detected in approximately 21.5 kb (i.e., 1 SNP every 335 bp). The level of polymorphism is highly variable among the different genes studied. Fifty percent of the genes studied contained no sequence polymorphism, whereas most SNPs detected were located in only 2 genes. As expected, taking into account a synthetic line created with a wild Triticum tauschii parent increases the level of polymorphism (101 SNPs; 1 SNP every 212 bp). The detected SNPs are available at http://urgi.versailles.inra.fr/GnpSNP">http://urgi.versailles.inra.fr/GnpSNP. Data on linkage disequilibrium (LD) are still preliminary. They showed a significant level of LD in the 2 most polymorphic genes. To conclude, the genome size of hexaploid wheat and its low level of polymorphism complicate SNP discovery in this species.
关于六倍体面包小麦单核苷酸多态性（SNP）的信息仍然匮乏。本研究的目的是检测小麦中的SNP并研究其频率。使用了来自世界各地不同来源的26个面包小麦品系。从21个基因中获得了特异性PCR产物并直接进行测序。通过这些序列的比对发现了SNP。在该样本中观察到的总体序列多态性似乎较低；在约21.5 kb中检测到64个单碱基多态性（即每335 bp有1个SNP）。在所研究的不同基因中，多态性水平差异很大。所研究的基因中有50%没有序列多态性，而检测到的大多数SNP仅位于2个基因中。正如预期的那样，考虑到一个含有野生节节麦亲本的合成品系会增加多态性水平（101个SNP；每212 bp有1个SNP）。检测到的SNP可在http://urgi.versailles.inra.fr/GnpSNP获取。关于连锁不平衡（LD）的数据仍然是初步的。它们在2个多态性最高的基因中显示出显著的LD水平。总之，六倍体小麦的基因组大小及其较低的多态性水平使得在该物种中发现SNP变得复杂。
