ARS | Publication request: HIGH-THROUGHPUT MARKER IDENTIFICATION AND MAPPING IN WHEAT USING TRAPS (TARGET REGION AMPLIFICATION POLYMORPHISM).

Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 15, 2003
Publication Date: January 10, 2004
Citation: Faris, J.D., Xu, S.S., Liu, Z., Hu, J. 2004. High-throughput marker identification and mapping in wheat using traps (target region amplification polymorphism). Plant and Animal Genomes XII Conference Abstracts. January 10-14, 2004. San Diego, CA. p. 120.

Technical Abstract: High-throughput marker technologies are necessary for the rapid mapping of plant genomes to identify genomic regions harboring genes governing desirable traits and for marker-assisted selection. The recently developed TRAP technique employs an 18mer random primer in combination with a fixed 18mer primer designed based on known EST sequences to amplify genomic fragments. The random primers are 3' end-labeled with IR dye 700 or IR dye 800 for autodetection on a Li-Cor Global DNA Sequencer. We applied the TRAP technique to two sets of tetraploid Langdon durum-Triticum dicoccoides (LDN-DIC) disomic chromosome substitution lines to determine the number and chromosomal locations of polymorphic TRAP markers. The LDN-DIC (PI481521) disomic substitution set has been characterized with 37 PCR reactions resulting in the identification of 642 TRAP markers. The markers were distributed among all 14 chromosomes, and the number per chromosome ranged from 19 (3B) to 72 (7A). The second disomic substitution set [LDN-DIC (PI4787420)] has been partially characterized with 91 polymorphic markers identified from five PCR reactions. On average, 17 polymorphic markers were observed per PCR reaction in the LDN-DIC lines. In addition, we assessed the number of polymorphic markers and genetic map locations of TRAPs in a hexaploid wheat recombinant inbred population derived from BR34 x Grandin. In this population, we observed an average of 20 polymorphic markers per PCR reaction. Linkage and genomic distribution of TRAP marker loci will be discussed. The TRAP markers are useful for genome characterization, tagging desirable genes, and high-throughput mapping of wheat populations.