title: Tetrasomic recombination is surprisingly frequent in allotetraploid Arachis.
abstract: Arachis hypogaea L. (cultivated peanut) is an allotetraploid (2n = 4x = 40) with an AABB genome type. Based on cytogenetic studies it has been assumed that peanut and wild-derived induced AABB allotetraploids have classic allotetraploid genetic behavior with diploid-like disomic recombination only between homologous chromosomes, at the exclusion of recombination between homeologous chromosomes. Using this assumption, numerous linkage map and quantitative trait loci studies have been carried out. Here, with a systematic analysis of genotyping and gene expression data, we show that this assumption is not entirely valid. In fact, autotetraploid-like tetrasomic recombination is surprisingly frequent in recombinant inbred lines generated from a cross of cultivated peanut and an induced allotetraploid derived from peanut's most probable ancestral species. We suggest that a better, more predictive genetic model for peanut is that of a "segmental allotetraploid" with partly disomic, partly tetrasomic genetic behavior. This intermediate genetic behavior has probably had a previously overseen, but significant, impact on the genome and genetics of cultivated peanut.
authors.affiliation: Embrapa Genetic Resources and Biotechnology, Brasília, DF 70770-917, Brazil Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602-6810.
authors.forename: Soraya
authors.initials: S
authors.lastname: Leal-Bertioli
authors.affiliation: Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Shirasawa
authors.affiliation: Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602-6810.
authors.forename: Brian
authors.initials: B
authors.lastname: Abernathy
authors.affiliation: Embrapa Genetic Resources and Biotechnology, Brasília, DF 70770-917, Brazil.
authors.forename: Marcio
authors.initials: M
authors.lastname: Moretzsohn
authors.affiliation: Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602-6810.
authors.forename: Carolina
authors.initials: C
authors.lastname: Chavarro
authors.affiliation: Department of Horticulture, University of Georgia, Tifton, Georgia 31973.
authors.forename: Josh
authors.initials: J
authors.lastname: Clevenger
authors.affiliation: Department of Horticulture, University of Georgia, Tifton, Georgia 31973.
authors.forename: Peggy
authors.initials: P
authors.lastname: Ozias-Akins
authors.affiliation: Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602-6810.
authors.forename: Scott
authors.initials: S
authors.lastname: Jackson
authors.affiliation: University of Brasília, Institute of Biological Sciences, 70910-900 Brasília, DF, Brazil Center for Applied Genetic Technologies, University of Georgia, Athens, Georgia 30602-6810 bertioli@uga.edu.
authors.forename: David
authors.initials: D
authors.lastname: Bertioli
mesh_terms: D010367:Arachis / Q000235:genetics*; D032461:Chromosomes, Plant / Q000235:genetics; D008040:Genetic Linkage; D008957:Models, Genetic; D040641:Quantitative Trait Loci; D011995:Recombination, Genetic; D058670:Tetrasomy
keywords: Arachis; groundnut; induced allotetraploid; peanut; segmental genetics; tetrasomic genetics