A mutation is a change in the structure or amount of an organisms genetic material. The individual affected is called a mutant There are four main types of genetic mutations that occur in humans.
Substitution
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This is when one base in the DNA is substituted with another. this is a "point mutation" as only one amino acid in the chain is affected although this dramatically changes the protein formed and can have large effects such as producing haemoglobin s and suffering from sickle cell anaemia |
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Inversion
This is when two adjacent bases in the DNA strand swap. This is also a "point mutation" but just like substitution it can have drastic effects on an individual
Deletion
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This is when one base in the DNA strand is removed or "deleted" altogether. This is called a "frameshift" as it affects all the other amino acids transcribed after the mutation. This can cause non-functional protiens that are completely different from the ones intended and can cause massive problems such as Phenylketonuria. |
Insertion
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This is when an extra base is added somewhere along the DNA strand and is also a "frameshift" mutation. Just like deletion it can cause big problems.
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