title: Linkage disequilibrium and genome-wide association analysis for anthocyanin pigmentation and fruit color in eggplant.
abstract: BACKGROUND
  The genome-wide association (GWA) approach represents an alternative to biparental linkage mapping for determining the genetic basis of trait variation. Both approaches rely on recombination to re-arrange the genome, and seek to establish correlations between phenotype and genotype. The major advantages of GWA lie in being able to sample a much wider range of the phenotypic and genotypic variation present, in being able to exploit multiple rounds of historical recombination in many different lineages and to include multiple accessions of direct relevance to crop improvement.
  
  
  RESULTS
  A 191 accessions eggplant (Solanum melongena L.) association panel, comprising a mixture of breeding lines, old varieties and landrace selections originating from Asia and the Mediterranean Basin, was SNP genotyped and scored for anthocyanin pigmentation and fruit color at two locations over two years. The panel formed two major clusters, reflecting geographical provenance and fruit type. The global level of linkage disequilibrium was 3.4 cM. A mixed linear model appeared to be the most appropriate for GWA. A set of 56 SNP locus/phenotype associations was identified and the genomic regions harboring these loci were distributed over nine of the 12 eggplant chromosomes. The associations were compared with the location of known QTL for the same traits.
  
  
  CONCLUSIONS
  The GWA mapping approach was effective in validating a number of established QTL and, thanks to the wide diversity captured by the panel, was able to detect a series of novel marker/trait associations.
authors.forename: Fabio
authors.initials: F
authors.lastname: Cericola
authors.affiliation: Dipartimento di Scienze Agrarie, Forestali e Alimentari (DISAFA) - Plant Genetics and Breeding, University of Torino, Largo P, Braccini 2, I-10095 Grugliasco, Torino, Italy. ezio.portis@unito.it.
authors.forename: Ezio
authors.initials: E
authors.lastname: Portis
authors.forename: Sergio
authors.initials: S
authors.lastname: Lanteri
authors.forename: Laura
authors.initials: L
authors.lastname: Toppino
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Barchi
authors.forename: Nazzareno
authors.initials: N
authors.lastname: Acciarri
authors.forename: Laura
authors.initials: L
authors.lastname: Pulcini
authors.forename: Tea
authors.initials: T
authors.lastname: Sala
authors.forename: Giuseppe Leonardo
authors.initials: GL
authors.lastname: Rotino
mesh_terms: D000872:Anthocyanins / Q000378:metabolism*; D002874:Chromosome Mapping; D005638:Fruit / Q000378:metabolism*; D018745:Genome, Plant / Q000235:genetics; D023281:Genomics; D005838:Genotype; D015810:Linkage Disequilibrium; D018895:Microsatellite Repeats / Q000235:genetics; D010858:Pigmentation / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D032323:Solanum melongena / Q000235:genetics* / Q000378:metabolism*; D026801:Synteny / Q000235:genetics
chemical_list: D000872:Anthocyanins