44 lines
1.7 KiB
Markdown
44 lines
1.7 KiB
Markdown
# Point Mutations
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Write a program that can calculate the Hamming difference between two DNA strands.
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A mutation is simply a mistake that occurs during the creation or
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copying of a nucleic acid, in particular DNA. Because nucleic acids are
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vital to cellular functions, mutations tend to cause a ripple effect
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throughout the cell. Although mutations are technically mistakes, a very
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rare mutation may equip the cell with a beneficial attribute. In fact,
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the macro effects of evolution are attributable by the accumulated
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result of beneficial microscopic mutations over many generations.
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The simplest and most common type of nucleic acid mutation is a point
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mutation, which replaces one base with another at a single nucleotide.
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By counting the number of differences between two homologous DNA strands
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taken from different genomes with a common ancestor, we get a measure of
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the minimum number of point mutations that could have occurred on the
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evolutionary path between the two strands.
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This is called the 'Hamming distance'
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GAGCCTACTAACGGGAT
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CATCGTAATGACGGCCT
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^ ^ ^ ^ ^ ^^
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The Hamming distance between these two DNA strands is 7.
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# Implementation notes
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The Hamming distance is only defined for sequences of equal length. Hence you
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may assume that only sequences of equal length will be passed to your hamming
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distance function.
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Check out
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[Exercism Help](http://help.exercism.io/getting-started-with-lisp.html)
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for instructions to get started writing Common Lisp. That page will
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explain how to install and setup a Lisp implementation and how to run
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the tests.
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## Source
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The Calculating Point Mutations problem at Rosalind [view source](http://rosalind.info/problems/hamm/)
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