Search

Genome-wide association studies are powerful tools to elucidate the genome-to-phenomerelationship. In order to explain most of the observed heritability of a phenotypic trait, asufficient number of individuals and a large set of genetic variants must be examined. Thedevelopment of high-throughput technologies and cost-efficient resequencing of completegenomes have enabled the genome-wide identification of genetic variation at large scale.As such, almost all existing genetic variation becomes available, and it is now possible toidentify rare genetic variants in a population sample. Rare genetic variants that were usuallyfiltered out in most genetic association studies are the most numerous genetic variationsacross genomes and hold great potential to explain a significant part of the missingheritability observed in association studies. Rare genetic variants must be identified withhigh confidence, as they can easily be confounded with sequencing errors. In this study,we used a pre-filtered data set of 1,014 purePopulus trichocarpaentire genomes toidentify rare and common small genetic variants across individual genomes. We comparedvariant calls betweenPlatypusandHaplotypeCallerpipelines, and we further applied strictqualityfilters for improved genetic variant identification. Finally, we only retained geneticvariants that were identified by both variant callers increasing calling confidence. Based onthese shared variants and after stringent qualityfiltering, we found high genomic diversity inP. trichocarpagermplasm, with 7.4 million small genetic variants. Importantly, 377k non-synonymous variants (5% of the total) were uncovered. We highlight the importance ofgenomic diversity and the potential of rare defective genetic variants in explaining asignificant portion ofP. trichocarpa's phenotypic variability in association genetics. Theultimate goal is to associate both rare and common alleles with poplar's wood quality traitsto support selective breeding for an improved b

Genome-wide association studies are powerful tools to elucidate the genome-to-phenomerelationship. In order to explain most of the observed heritability of a phenotypic trait, asufficient number of individuals and a large set of genetic variants must be examined. Thedevelopment of high-throughput technologies and cost-efficient resequencing of completegenomes have enabled the genome-wide identification of genetic variation at large scale.As such, almost all existing genetic variation becomes available, and it is now possible toidentify rare genetic variants in a population sample. Rare genetic variants that were usuallyfiltered out in most genetic association studies are the most numerous genetic variationsacross genomes and hold great potential to explain a significant part of the missingheritability observed in association studies. Rare genetic variants must be identified withhigh confidence, as they can easily be confounded with sequencing errors. In this study,we used a pre-filtered data set of 1,014 purePopulus trichocarpaentire genomes toidentify rare and common small genetic variants across individual genomes. We comparedvariant calls betweenPlatypusandHaplotypeCallerpipelines, and we further applied strictqualityfilters for improved genetic variant identification. Finally, we only retained geneticvariants that were identified by both variant callers increasing calling confidence. Based onthese shared variants and after stringent qualityfiltering, we found high genomic diversity inP. trichocarpagermplasm, with 7.4 million small genetic variants. Importantly, 377k non-synonymous variants (5% of the total) were uncovered. We highlight the importance ofgenomic diversity and the potential of rare defective genetic variants in explaining asignificant portion ofP. trichocarpa's phenotypic variability in association genetics. Theultimate goal is to associate both rare and common alleles with poplar's wood quality traitsto support selective breeding for an improved b