Translocations involve transfer of non-homologous pieces of DNA between chromosomes. They occur in the same way as inversions and the consequences are similar. Occasionally gametes may be formed without any reduction of chromosome number. Plants are much more tolerant of such major chromosome alterations than most animals and such events seem to have been relatively common in plant evolution. This shows the consequences of errors in crossing-over after chromosome pairing during meiosis.
Some genes affect more than one feature in the phenotype.
For example a plant that lacks a functional gene involved in synthesis of abscisic acid has leaves that wilt easily and seeds that do not become dormant in the normal way. This is an example of a pleiotropic effect. Phenotypic characters may require appropriate alleles of several genes in order to be expressed. Flower color is often determined by enzymes that hydroxylate anthocyanin molecules at various positions. However, if genes for one or more enzymes early in flavonoid metabolism are not functional, the pigment may not be formed at all.