Accession-Specific Haplotypes of the Internal Transcribed Spacer Region in Arabidopsis thaliana-A Means for Barcoding Populations

作者：Simon Uwe K^*; Trajanoski Slave; Kroneis Thomas; Sedlmayr Peter; Guelly Christian; Guttenberger Helmut

来源：Molecular Biology and Evolution, 2012, 29(9): 2231-2239.

DOI：10.1093/molbev/mss093

• Arabidopsis
• barcoding
• concerted evolution
• intragenomic polymorphisms
• ITS
• population genetics

Eukaryote genomes contain multiple copies of nuclear ribosomal DNA (nrDNA) harboring both highly conserved and variable regions. This has made nrDNA the most popular genetic marker for phylogenetic studies and the region of choice for barcoding projects. Furthermore, many scientists believe that all copies of nrDNA within one nucleus are practically identical due to concerted evolution. Here, we investigate the model plant species Arabidopsis thaliana for intragenomic variation of the internal transcribed spacer (ITS) region of nrDNA. Based on a modified deep sequencing approach, we provide a comprehensive list of ITS polymorphisms present in the two most widely used accessions of A. thaliana Col-0 and Ler. Interestingly, we found that some polymorphisms are shared between these genetically very distinct accessions. On the other hand, the high number of accession-specific polymorphisms shows that each accession can be clearly and easily characterized by its specific ITS polymorphism patterns and haplotypes. Network analysis based on the detected haplotypes demonstrates that the study of ITS polymorphism patterns and haplotypes is an extremely powerful tool for population genetics. Using the methods proposed here, it will now be possible to extend the traditionally species-bound barcoding concept to populations.

• 出版日期2012-9