Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Theoretical aspects of applying sib—pair linkage tests to livestock species | Genet Sei Evol 1992 24 29-42 Elsevier INRA 29 Original article Theoretical aspects of applying sib-pair linkage tests to livestock species KU Gotz1 L Ollivier2 1 Institut fur Tierzucht und Haustiergenetik der Universitat Gottingen Albrecht-Thaer Weg 1 D-3400 Gottingen Germany 2 Institut National de la Recherche Agronomique Station de Génétique Quantitative et Appliquée 78352 Jouy-en-Josas Cedex France Received 26 March 1991 accepted 12 December 1991 Summary - The Haseman-Elston HE sib-pair linkage test in its original form is computationally simple but suffers from low power. With the advent of highly polymorphic markers the exclusive use of fully informative matings ie matings where the number of genes identical by descent for any sib pair can be inferred without error for the HE test becomes feasible. This article examines the influence of highly polymorphic marker systems 5 alleles large family sizes 6 full-sibs and hierarchical breeding structures mating ratio of 25 on the power of the HE test by means of simulation studies. Simulations are performed under the assumption that the costs of marker genotyping are a limiting factor for marker-QTL linkage studies. Consequently the total number of individuals parents and offspring typed is fixed at 5 000 in each of the situations compared. The results show that the power of the HE test is considerably increased when both highly polymorphic markers and large full-sib families are available. For example for a locus explaining 8 of the phenotypic variance the power of the test increases from 14 to 74 if the locus has 5 alleles instead of 2 and sibship size is 6 instead of 2. Hierarchical breeding structures tend to further increase the power of the test for the example given from 74 to 79 . linkage marker gene quantitative trait locus Haseman Elston test power Résumé - Aspects théoriques de 1 application du test de liaison génétique par les couples de germains aux espềces animates domestiques. Dans sa forme originelle .