BIGGER

Individuals duplicated by allopolyploidy have an hybridisation of two different species induce a change in the number of chromosome sets. This event may cause genomic under-dominance. In contrast, individuals duplicated by autopolyploidy have an hybridisation between two identical species, but genomic under-dominance has not yet been observed.

The ancestor of the apple tree (Malus domestica) had a whole genome duplication (WGD) 27 million years ago. The duplicated chromosomal fragments were analysed. Imbalances in the proportion of mapped QTLs, transposable element coverage, gene expression levels and DNA methylation were observed between homologous chromosome fragments. These imbalances suggest a subchromosomal dominance.

In this project we will investigate duplicated genes where one copy is systematically differentially expressed. We will study in detail their transposable element environments and the DNA methylation around these ohnologous genes. We will also investigate the biological and molecular functions and metabolic pathways in which these ohnologous genes are implicated.

We will also carry out similar research on the Pear tree, an organism that had the last WGD common to the Apple tree. We will investigate whether the imbalances present in apple are also present in pear. Depending on the resources available during the project, we would also like to carry out research on Quince and Sorb.