EHJ352H1 Lecture Notes - Lecture 14: Effective Population Size, Linkage Disequilibrium, Allele Frequency
12 Oct 2016
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Document Summary
Last lecture we talked about patterns of linkage disequilibrium - looking at human genome to gain information about heterogeneity of the genome. Rate of recombination is very heterogeneous across the genome. This translates into some regions having big blocks of high linkage disequilibrium. Even within humans there is variation to the extent to which recombination is occurring at these hot spots. We see variation within and between species. Different alleles related to the transcription factor that either recognize these sequence motifs or not. Most recombination occurs in hotspots if they recognize motif. Turns out that there is sort of a paradox. Recombination initiated gets a double strand break - corrected by the other strand - converted out by other allele. Sets up a scenario where there should be rapid evolution of these recombination hotspots. Prdm9 must have rapid evolution to recognize a new set of hotspots. Problem becomes that you start losing recombination across the genome.
