Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 9/29/2004
Publication Date: 1/1/2005
Citation: Kindiger, B.K. 2005. Quasi-palindromes and the genetic analysis of complex polyploid grasses. Plant and Animal Genome Conference Proceedings. p. 267.
Interpretive Summary: Abstract Only
Technical Abstract: The genetic or molecular analysis of polyploid grasses is an elusive and complex endeavor made more difficult by unpredictable chromosome pairing and disjunction events during meiosis, the occurrence of multiple alleles in the polyploid genome and a need for large segregating populations. As consequence, an approach that could efficiently generate informative markers for the genetic analysis of polyploids would be quite useful. It has been well established that polyploids can possess major structural genome rearrangements following polyploidization. If such rearrangements occur in polyploid genomes, by what method could such sites be identified and could these sites be used to assist genetic analysis in a polyploid species. Palindromes are one type of genome arrangement theoretically considered to be present in polyploid species and can be sustained due to the polyploid genome condition. Consequently, such site may be scattered throughout a polyploid genome. Utilizing a series of sequence loci obtained from Oryza sativa, Triticum aestivum, Lolium perenne, Bromus tectorum, Anisantha sterilis, and Zoysia japonica genomes, 46 single primers of 20-25 nt length were identified to be associated with palindrome or near-palindrome sequence sites within the complex genome of Poa arachnifera (Texas bluegrass). Similar analysis were performed on Poa pratensis, Poa secunda, Bromus inermis, Thinopyrum ponticum and Dactylis glomerata and each indicated the universal presence of palindrome regions. The ability to identify palindrome-type sequences in the genomes of complex polyploids should provide a useful approach for genotyping and performing markers-assisted-selection studies in polyploid grasses.