RT Journal Article SR Electronic T1 Genetic Variation among Koshu (Vitis vinifera L.) Accessions Generated by Retrotransposon Insertion into Genome JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 490 OP 496 DO 10.5344/ajev.2009.60.4.490 VO 60 IS 4 A1 Keiko Fujita A1 Mamiko Shimazaki A1 Terumi Furiya A1 Tsutomu Takayanagi A1 Shunji Suzuki YR 2009 UL http://www.ajevonline.org/content/60/4/490.abstract AB Koshu (Vitis vinifera L.) is indigenous to Japan, where it is the most popular cultivar for white winemaking. Koshu grapevines have not been systematically classified according to yield, fruit quality, morphologic phenotype, and genetic variation. We report here the genetic variation among Koshu accessions classified by the region where they were cultivated. Eight retroelements were selected for inter-retrotransposon amplified polymorphism (IRAP) analysis and 16 retrotransposon-specific primers were designed. Polymerase chain reaction (PCR) using 136 primer sets amplified 731 PCR bands. Thirty-five polymorphic bands among Koshu accessions were identified by PCR using 24 primer sets. Individual grapevines from the same accession exhibited monomorphic band patterns for the primer sets. Cluster analysis based on polymorphic band patterns identified by IRAP analysis demonstrated that the Koshu accessions tested might be classified into three genetic groups. Results indicate that genetic variation among accessions might be generated by retrotransposon insertion into the Koshu genome.