02909naa a2200265 a 450000100080000000500110000800800410001902200140006002400380007410000190011224501130013126000090024450005210025352016080077465000240238265300170240665300110242365300280243465300120246270000150247470000150248970000170250470000190252177301030254010643102023-09-14       2023    bl uuuu     u00u1 u    #d  a2352-40737 a10.1016/j.plgene.2023.1004302DOI1 aGIORELLO, F.M.  aEvaluating the potential of XP-GWAS in EucalyptusbLeaf heteroblasty as a case study.h[electronic resource]  c2023  aArticle history: Received 3 February 2023, Revised 24 July 2023, Accepted 11 August 2023, Available online 22 August 2023, Version of Record 31 August 2023. -- Correspondence:   Giorello, F.M.; Espacio de Biología Vegetal del Noreste, Centro Universitario Regional Noreste, sede Tacuarembó, Universidad de la República, Tacuarembó, Uruguay; email:facundo.giorello@cut.edu.uy  -- FUNDING: This work was supported by grant of the Ministerio de Educación y Cultura, Uruguay (Fondo Vaz Ferreira 173, DICyT, MEC). --  aABSTRACT.- Eucalyptus is one of the mainstays of the forest industry, contributing high-quality raw materials for pulp, paper, wood, and energy production. The typical approaches to reveal the genetic basis of important traits include classical Quantitative Trait Locus (QTL) mapping and Genome-Wide Association Studies (GWAS) approaches, but these are typically expensive and time-consuming. Here we evaluate the potential of Extreme-Phenotype GWAS (XP-GWAS) to identify candidate genes underlying a quantitative trait in Eucalyptus, using the timing of leaf heteroblasty as a case study. XP-GWAS involves genotyping pools of individuals grouped by extreme and opposed phenotypes from a population or a diversity panel and studying their allele frequency. Using a previous phenotyped trial of E. globulus, we sequenced pools of 50 individuals that notably differ in the onset of adult foliage. Since the genetic basis of heteroblasty is well understood, we first searched for previously identified genes. Secondly, we searched for new candidate genes and also evaluated the copy number variation (CNVs) that may be involved in this process. We found marginally significant SNPs associated with previously described microRNAs, and interesting new non-coding RNAs. Disease resistance genes were also uncovered, probably as a consequence of indirectly selecting resistant trees, although a possible interaction between resistance and heteroblasty cannot be disregarded either. Our work shows the utility and limitations of XP-GWAS analysis to explore the genetic basis of Eucalyptus. © 2023 Elsevier B.V.  aEUCALYPTUS GLOBULUS  aHeteroblasty  aMiR156  aSISTEMA FORESTAL - INIA  aXP-GWAS1 aFARIAS, J.1 aBASILE, P.1 aBALMELLI, G.1 aDA SILVA, C.C.  tPlant Gene. December 2023, Volume 36, article 100430. https://doi.org/10.1016/j.plgene.2023.100430