GOLD - Background Information
What is linkage disequilibrium?
As ancestral haplotypes propagate through a population, their
physical length is reduced by recombination events. Recombination
events between markers separated by very short distances are
very rare. Thus, genotypes at nearby markers are not independent
and their association may reflect ancestral founding haplotypes.
Why is linkage disequilibrium important?
Traditional linkage analysis, based on allele sharing between
relatives, identifies broad chromosomal regions that are likely
to contain disease genes. However, the resolution of these methods
is limited by recombination events in typical pedigrees. Methods
based on linkage disequilibrium take into account ancestral recombination
and may be better suited to the identification of positional
What are the advantages of a graphical display tool?
Linkage disequilibrium is commonly described by pair-wise
measures. However, the number of pair-wise statistics rises exponentially
with the number of markers so that their interpretation is cumbersome
for dense maps. As a consequence, it is exceedingly difficult
to draw meaningful conclusions from tabular summaries of disequilibrium