Blocks of Limited Haplotype Diversity
Newton E Morton, University of Southampton, Southampton, UK
Published online: December 2007
DOI: 10.1002/9780470015902.a0006251.pub2
Abstract
A haplotype block is a DNA sequence containing polymorphisms in strong linkage disequilibrium (LD) and with low haplotype
diversity, separated from other blocks by steps of low LD with high haplotype diversity. Haplotype blocks may be as short
as 2 kb or more than 150 kb, depending both on block definition and the spacing of LD cold spots, which tend to be shorter
than blocks. Haplotype diversity measured by the effective number of haplotypes is said to be low if smaller than the number
of polymorphisms defining the haplotype. To be useful in genetic analysis, the haplotype should be shorter than a typical
block.
Keywords: haplotype block; linkage disequilibrium; haplotype diversity; linkage disequilibrium map; selective sweep
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