Mutations in normal cell division are due to changes occurring within DNA itself or in the replication/cell division process. Changes within the DNA molecule are referred to as ‘point mutations’ since they occur in a small portion of the DNA but may still have significant effect because they change the ‘meaning of the code’. Point mutations can be due to damage from:
· solar radiation
· chemicals
· viruses
· temperature stress from heat, cold
· physical stress such as severe pruning, or insect damage
· or replication error causing a shift in DNA sequences so it no longer makes sense.