next.jpgmore_grey.jpgLife Changes. Mutation. Causes of mutationshelp.jpgJoin56x56.jpghome.jpg The main cause of mutation is when DNA is copied.

You can go here to find out more about DNA.

DNA is made from two spirals winding round each other with special links between them.
It's a bit like a twisted ladder.
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The DNA code in the links between the two spirals.

Each link is made of two bases. The bases are A, C, G and T.
They always come in base pairs, A-T, C-G, G-C and T-A.

When DNA gets copied (or replicated) the two spirals are split apart.
The base-pairs are separated.