linkage disequilibrium

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link·age dis·e·qui·lib·ri·um

a state involving two loci in which the probability of a joint gamete is not equal to the product of the probabilities of the constituent genes. The difference between these quantities is the increase of the disequilibrium; there are many causes of the disequilibrium.
Farlex Partner Medical Dictionary © Farlex 2012

link·age dis·e·qui·li·bri·um

(lingk'ăj dis-ē'kwi-lib'rē-ŭm)
A state involving two loci in which the probability of a joint gamete is not equal to the product of the probabilities of the constituent genes. The difference between these quantities is the increase of the disequilibrium; there are many causes of the disequilibrium.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

linkage disequilibrium

The occurrence of combination of genes (linkages) in a population more often, or less often, than would be expected from their distance apart in the genome.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

linkage disequilibrium

a nonrandom association of alleles at different loci in a population, as is produced when two loci are closely linked and selection operates to keep certain gene combinations together.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
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In case where alleles are in linkage equilibrium and the recombination history is different for haplotypes but mutation history is the same, both D' and r2 will be zero (Fig.
The Bonferroni test found that all loci were in linkage equilibrium in the bromeliad populations collected in both P.
It will be interesting to see if the pair of loci (Med 362 and Med 722) that showed some evidence of linkage (significant deviation from linkage equilibrium), when mapped, will be close together in the same linkage group.
Linkage equilibrium among tightly linked RFLPs and the Ms locus in open-pollinated onion populations.
Importantly, in all four mixed ancestry river populations deviations from linkage equilibrium are quite strong and highly significant, although deviations from Hardy-Weinberg equilibrium are clearly significant in just a single population (Table 3).
The small negative deviations from this prediction arose because finite (rather then infinitesimal) loci were simulated and because the loci were not always in linkage equilibrium as assumed by Robertson (1960).
With linkage equilibrium, the net epistasis contributed by the tester (Melchinger, 1988) is zero because each of the four gametes occurs at a frequency of 1/4.
If all the loci are in linkage equilibrium, then the frequencies of combinations of alleles are products of allele frequencies, and
Additive variance assuming linkage equilibrium was [MATHEMATICAL EXPRESSIONS NOT REPRODUCIBLE IN ASCII] in the initial generation.
Bazykin (1973) provides the conditions for the existence of a migration-selection balance using a two-locus model of stabilizing selection with equal migration rates under the assumption of linkage equilibrium. For more than two loci, however, an approach such as his is prohibitive because of the complexity of the analysis.
Repeated cycles of intermating moves the resulting population toward linkage equilibrium, breaking up linkages among alleles that were previously associated because of common ancestry.
The observed variance in the distribution of allelic mismatches ([V.sub.o]) can be compared with the variance expected at linkage equilibrium ([V.sub.e]) to provide a measure of multilocus linkage disequilibrium.