Identifying Genetic Causes of Hybrid Necrosis in Arrabidopsis lyrata

Abstract: Deleterious gene interactions due to accumulation of individual genetic variations between different lineages are a cause of population diversification by creating reproductive barriers that ultimately lead to differentiation of species. One type of deleterious interactions is called “hybrid necrosis”, in which epistatic interactions between some plant immunity genes (usually very variable) cause autoimmunities that produce a necrotic and dwarf phenotype. Hybrid necrosis has been widely studied in several plant species, such as Arabidopsis thaliana and many gene interactions were found for that plant. This study tests the applicability of these results on a close relative, A. lyrata, by crossing individuals from different populations and genotyping F2 progeny with polymorphic markers close to homologous sequences to those involved in hybrid necrosis in A. thaliana. Results suggest the possibility of a homologous gene to DM8 or DM9 in chromosome 7 to be involved in formation of hybrid necrosis.