title: Exon-primed intron-crossing (EPIC) PCR markers of Helicoverpa armigera (Lepidoptera: Noctuidae).
abstract: Applying microsatellite DNA markers in population genetic studies of the pest moth Helicoverpa armigera is subject to numerous technical problems, such as the high frequency of null alleles, occurrence of size homoplasy, presence of multiple copies of flanking sequence in the genome and the lack of PCR amplification robustness between populations. To overcome these difficulties, we developed exon-primed intron-crossing (EPIC) nuclear DNA markers for H. armigera based on ribosomal protein (Rp) and the Dopa Decarboxylase (DDC) genes and sequenced alleles showing length polymorphisms. Allele length polymorphisms were usually from random indels (insertions or deletions) within introns, although variation of short dinucleotide DNA repeat units was also detected. Mapping crosses demonstrated Mendelian inheritance patterns for these EPIC markers and the absence of both null alleles and allele 'dropouts'. Three examples of allele size homoplasies due to indels were detected in EPIC markers RpL3, RpS6 and DDC, while sequencing of multiple individuals across 11 randomly selected alleles did not detect indel size homoplasies. The robustness of the EPIC-PCR markers was demonstrated by PCR amplification in the related species, H. zea, H. assulta and H. punctigera.
authors.affiliation: Centre for Environmental Stress and Adaptation Research, Department of Genetics, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia. weetek.tay@csiro.au
authors.forename: W T
authors.initials: WT
authors.lastname: Tay
authors.forename: G T
authors.initials: GT
authors.lastname: Behere
authors.forename: D G
authors.initials: DG
authors.lastname: Heckel
authors.forename: S F
authors.initials: SF
authors.lastname: Lee
authors.forename: P
authors.initials: P
authors.lastname: Batterham
mesh_terms: D000483:Alleles; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D004296:Dopa Decarboxylase / Q000737:chemistry / Q000235:genetics; D005091:Exons / Q000235:genetics*; D018628:Gene Dosage; D005819:Genetic Markers; D023281:Genomics / Q000379:methods; D040582:Inheritance Patterns; D007438:Introns / Q000235:genetics*; D008969:Molecular Sequence Data; D009036:Moths / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012269:Ribosomal Proteins / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D005819:Genetic Markers; D012269:Ribosomal Proteins; D004296:Dopa Decarboxylase