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The origin of human genetic variability from
cross-species comparisons: The truth about Blast
Mutational hotspots at CG dinucleotides
You're particularly interested in determining where mutations occur in human DNA. One area you want to scrutinize is DNA near CG dinucleotides. In human cells, many cytosines 5' to guanines are methylated. This has the side-effect of increasing the rate of mutagenesis, as methylcytosines spontaneously hydrolyze to thymines. Certainly these cytosines are sources of genome variability, but are the nearby regions also hypervariable?
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G T C G T T A
C A G C A A T
G T CmG T T A
C A G CmA A T
G T T G T T A
C A G CmA A T
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As luck would have it, a colleague comes up to you at a meeting after you've finished presenting your work on SNPs and says that she studies CG-rich regions in the chimpanzee genome. In the course of her work, she's accidentally run across a few sequences corresponding to human SNPs. She wants to know if they happen to be in the collection of human/chimp SNP regions you were just talking about.
How to answer her question?
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