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Preliminary ranking procedures for multilocus ordering.

D E Weeks·K Lange
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Abstract

N linked loci can be arranged in N!/2 possible orders. We describe two criteria for providing a preliminary ranking of the possible orders based on the N(N-1)/2 pairwise lod score curves for the loci. For a given order the first criterion is the sum of the N-1 maximal lod scores corresponding to the adjacent pairs of loci in the order. The second criterion is the minimum of a least-squares problem due to J.M. Lalouel (1977, Heredity 38(1): 61-77). This least-squares problem requires the maximum likelihood recombination fraction estimates and their standard errors. For N small it is feasible to evaluate these measures for every possible order. For N large we use a simulated annealing algorithm. This gives a fairly complete listing of the best-candidate orders without sampling every possible order. These ranking methods are applied to data from linkage groups on chromosomes 1, 6, 11, and 13.

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AlgorithmsBiometryChromosome MappingGenetic LinkageHumansLod ScoreJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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D E Weeks, K Lange. 1987. Preliminary ranking procedures for multilocus ordering.. https://doi.org/10.1016/0888-7543(87)90050-4

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