title: Waxy genes from spelt wheat: new alleles for modern wheat breeding and new phylogenetic inferences about the origin of this species.
abstract: OBJECTIVE
  Waxy proteins are responsible for amylose synthesis in wheat seeds, being encoded by three waxy genes (Wx-A1, Wx-B1 and Wx-D1) in hexaploid wheat. In addition to their role in starch quality, waxy loci have been used to study the phylogeny of wheat. The origin of European spelt (Triticum aestivum ssp. spelta) is not clear. This study compared waxy gene sequences of a Spanish spelt collection with their homologous genes in emmer (T. turgidum ssp. dicoccum), durum (T. turgidum ssp. durum) and common wheat (T. aestivum ssp. aestivum), together with other Asian and European spelt that could be used to determine the origin of European spelt.
  
  
  METHODS
  waxy genes were amplified and sequenced. Geneious Pro software, DNAsp and MEGA5 were used for sequence, nucleotide diversity and phylogenetic analysis, respectively.
  
  
  RESULTS
  Three, four and three new alleles were described for the Wx-A1, Wx-B1 and Wx-D1 loci, respectively. Spelt accessions were classified into two groups based on the variation in Wx-B1, which suggests that there were two different origins for the emmer wheat that has been found to be part of the spelt genetic make-up. One of these groups was only detected in Iberian material. No differences were found between the rest of the European spelt and the Asiatic spelt, which suggested that the Iberian material had a different origin from the other spelt sources.
  
  
  CONCLUSIONS
  The results suggested that the waxy gene variability present in wheat is undervalued. The evaluation of this variability has permitted the detection of ten new waxy alleles that could affect starch quality and thus could be used in modern wheat breeding. In addition, two different classes of Wx-B1 were detected that could be used for evaluating the phylogenetic relationships and the origins of different types of wheat.
authors.affiliation: Departamento de Genética, Escuela Técnica Superior de Ingeniería Agronómica y de Montes, Edificio Gregor Mendel, Campus de Rabanales, Universidad de Córdoba, CeiA3, ES-14071 Córdoba, Spain. ge2gugac@uco.es
authors.forename: Carlos
authors.initials: C
authors.lastname: Guzmán
authors.forename: Leonor
authors.initials: L
authors.lastname: Caballero
authors.forename: Luis M
authors.initials: LM
authors.lastname: Martín
authors.forename: Juan B
authors.initials: JB
authors.lastname: Alvarez
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D001947:Breeding; D004591:Electrophoresis, Polyacrylamide Gel; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011110:Polymorphism, Genetic; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D013214:Starch Synthase / Q000235:genetics* / Q000378:metabolism; D014908:Triticum / Q000235:genetics* / Q000378:metabolism
chemical_list: D010940:Plant Proteins; C060756:waxy protein, plant; D013214:Starch Synthase