Epigenetics is the study of heritable changes in gene expression that occur without a change in DNA sequence. In higher plants, these phenomena have economic relevance in the case of somaclonal variation: a genetic and phenotypic variation among clonally propagated plants from a single donor genotype. In oil palm (Elaeis guineensis Jacq), approximately 5% of somatic embryo-derived palms show abnormalities in their floral development. This variant phenotype offers a very interesting model, because somaclonal variation alters the expression of genes coding, directly or indirectly for the flower structure. Studies on genomic DNA methylation changes induced by tissue culture together with results from long term field studies have suggested that epigenetic mechanisms play an important role in the determination of somaclonal variation in oil palm. (Texte intégral)