By this invention, modification of the fatty acid composition of a plant seed may be achieved as a result of the activity of a DNA sequence foreign to the plant species to be modified. In particular, it has been found that a plant oil having a modified fatty acid composition can be obtained upon the expression of genes derived from plants of different species than the host plant, upon the expression of genes derived from bacteria, and from the transcription of anti-sense sequences which are complementary to endogenous genes of the plant host cell. In a preferred embodiment, transcription of the fatty acid modifying foreign DNA sequence is restricted to the developing seed tissues.
