tailieunhanh - Báo cáo sinh học: "Use of sib-pair linkage methods for the estimation of the genetic variance at a quantitative trait locus"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Use of sib-pair linkage methods for the estimation of the genetic variance at a quantitative trait locus | - Q ỰỤIN 1995 Genet Sei Evol 1995 27 97-110 Elsevier INRA nẾL íir ỉn nt Uí CAriSilquj Anlmajr _ MGltOĩxèaÓE p-76362 EN JHS S 97 Original article Use of sib-pair linkage methods for the estimation of the genetic variance at a quantitative trait locus H Hamann KU Gotz Bayerische Landesanstalt fur Tierzucht Prof Diirrwaechter-Platz I 85586 Grub Germany Received 26 August 1994 accepted 19 November 1994 Summary - Until recently the sib-pair linkage method of Haseman and Elston could only be used for the detection of linkage between a quantitative trait locus QTL and a marker locus. It was not possible to estimate the amount of genetic variance contributed by the QTL or its recombination fraction with the marker locus. With the advent of dense marker maps for nearly every domestic species every QTL should be located between 2 flanking markers. In this situation the Haseman-Elston test can be modified to estimate the variance of a putative QTL as well as its recombination fractions with the 2 flanking markers. In the present paper we derive 2 different estimation methods for the QTL variance based on the squared performance of full sibs in one only the QTL variance is estimated while in the other both the QTL variance and the recombination fractions are estimated. The method that estimates only the QTL variance turns out to be more powerful than the other. With respect to the estimation of QTL variance both methods give results close to the true values. However the estimation of recombination fractions resulted in an overall underestimation of the true parameters. sib-pair linkage quantitative trait locus genetic marker genetic variance recombination fraction Resume Emploi des methodes d evaluation des liaisons génétiques par les couples de germains pour estimer la variance génétique à un locus de caractère quantitatif. Jusqu a une période récente le test de liaison génétique de Haseman et Elston base sur les couples de germains ne pouvait être utilise que pour la mise en