Molecular genetics is essentially the study of the mechanisms and effects of trait inheritance at the molecular level. Cytogenetic analysis—the study of the numbers, structure, and organization of the chromosomes packaging the DNA within the cell nucleus—is important for understanding evolution, genetics, epigenetics, genetic recombination, and nuclear stability in all species. Oil palm is a perennial species mostly grown as a source of vegetable oil, although more recently it is also gaining popularity as a biofuel feedstock. Oil palm breeding programs were first initiated in Africa with the objective to obtain high-yielding materials for commercial planting. Whole-genome sequencing is a laboratory process that can reveal the complete DNA repertoire of an organism's genome, distributed in the nucleus, mitochondria, and chloroplasts. The reference oil palm genomes and high-density OP200K genotyping array has enabled the first genome-wide association study (GWAS) of mesocarp oil content in oil palm.