tailieunhanh - Báo cáo sinh học: "Quantitative trait loci mapping in dairy cattle: review and meta-analysis"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: Quantitative trait loci mapping in dairy cattle: review and meta-analysis | Genet. Sel. Evol. 36 2004 163-190 INRA EDP Sciences 2004 DOI gse 2003057 163 Original article Quantitative trait loci mapping in dairy cattle review and meta-analysis Mehar S. Khatkar Peter C. Thomson Imke Tammen Herman W. Raadsma Centre for Advanced Technologies in Animal Genetics and Reproduction ReproGen and Co-operative Research Centre for Innovative Dairy Products Faculty of Veterinary Science University of Sydney PMB 3 Camden NSW 2570 Australia Received 4 July 2003 accepted 29 October 2003 Abstract - From an extensive review of public domain information on dairy cattle quantitative trait loci QTL we have prepared a draft online QTL map for dairy production traits. Most publications 45 out of 55 reviewed reported QTL for the major milk production traits milk fat and protein yield and fat and protein concentration and somatic cell score. Relatively few QTL studies have been reported for more complex traits such as mastitis fertility and health. The collated QTL map shows some chromosomal regions with a high density of QTL as well as a substantial number of QTL at single chromosomal locations. To extract the most information from these published records a meta-analysis was conducted to obtain consensus on QTL location and allelic substitution effect of these QTL. This required modification and development of statistical methodologies. The meta-analysis indicated a number of consensus regions the most striking being two distinct regions affecting milk yield on chromosome 6 at 49 cM and 87 cM explaining and percent of the genetic variance of milk yield respectively. The first of these regions near marker BM143 affects five separate milk production traits protein yield protein percent fat yield fat percent as well as milk yield . quantitative trait loci dairy cattle review meta-analysis 1. INTRODUCTION A major objective of quantitative trait loci QTL studies is to find genes markers that can be implemented in breeding programs via marker assisted .