Gene mutations might arise during DNA replication; they include addition, deletion, substitution, inversion, duplication and translocation of bases
A gene mutation is a change to the base sequence of a DNA molecule. Several types exist, and they most often arise when DNA copies itself before cell division.
Real World
Sickle cell anaemia results from a single base substitution in the haemoglobin gene — an A is replaced by a T — changing one amino acid (glutamic acid to valine) and altering the shape of the entire protein.
Exam Focus
Learn all six mutation types with a one-word definition each — deletion and addition cause frameshifts, substitution does not.
Evaluation Scaffold
A four-step framework for high-quality evaluation. Use this for 'assess', 'evaluate', and 'to what extent' questions.
How well did you know this?