If the roll is between 1 through 18, inclusive, select
that nucleotide.
Otherwise, skip mutation and clone the genome
again.
Select the rolled
nucleotide in the sequence.
Roll to see what kind of mutation to perform.
Depending on the roll:
If the roll is between 1 through 14, inclusive, perform
a transition on the selected nucleotide.
If the roll is between 15 through 17, inclusive,
perform a complementing transversion on the selected
nucleotide to the base it pairs with.
Otherwise, perform the other transversion on
the selected nucleotide.
Select the correct amino acid for the new codon.
Depending on the change to the codon:
If the mutation caused a change in the amino acid being
coded, mark this mutation as lethal, and start
over with the genome from the previous iteration.
Otherwise, mark the mutation as non-lethal,
and continue with this new genome.