CONICET | Buscador de Institutos y Recursos Humanos

Background Unravelling the genetic arquitecture underlying phenotypic variation is a central issue in evolutionary biology. Genome-wide association (GWAS) is a powerful tool to study association between phenotype and the genotype. The Drosophila melanogaster reference panel (DGRP) [1] is an artificial population consisting of inbreed lines derived from a natural population that are fully sequenced, enabling the possibility of performing phenotype - genotype association mapping of quantitative traits. Oviposition preference (OP) is a complex trait that has paramount importance in model systems like Drosophila. The election of a suitable resource is crucial since determines the breeding site in which the progeny will develop since the larvae do not have the ability to move to a different resource. Our goal is to perform the first prediction of the genetic arquitecture of OP through the characterization of single nucleotide polymorphism (SNPs) that are associated with trait phenotypic variation. Materials and Methods To characterize OP natural genetic variation we measured the proportion of eggs laid in one of the resource offered to females in double choice experiments. Two combinations of resources were tested Vitis vinifera (grape, G) - Citrus aurantium (orange, O) and G - Solanum lycopersicum (tomato, T). GWAS was conducted with 1.450.201 segregation sites in 40 DGRP lines. Then, we selected five candidate genes for functional testing through mutant validation. Results The GWAS revealed a total of 84 SNPs at a significance threshold of p < 10-5. 64 SNPs were associated with variation in the combination G-O and 20 SNPs in the combination G-T (figure 1). There is no overlap of SNP between combinations. Validation tests confirmed the involvement of three out of five candidate genes tested, implying that the genes are part of the genetic networks involved in OP.