Plant & Animal Genomes XIII Conference

January 15-19, 2005
Town & Country Convention Center
San Diego, CA

International Equine Gene Mapping Workshop Report: The Phase III Linkage Map

M. Cecilia Penedo¹ , L V Millon¹ , D Bernoco² , E Bailey³ , M Binns⁴ , G Cholewinski⁵ , N Ellis⁶ , J Flynn⁷ , B Gralak⁸ , A Guthrie⁹ , T Hasegawa¹⁰ , G Lindgren¹¹ , L A Lyons¹² , K H Roed¹³ , J E Swinburne¹⁴ , T Tozaki¹⁵

¹  Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California, Davis, CA 95616, USA

²  Stormont Laboratories Inc., Woodland, CA 95776, USA

³  MH Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY 40546, USA

⁴  The Royal Veterinary College, London, United Kingdom

⁵  Horse Genetic Markers Laboratory, Agricultural University of Poznan, Poznan, Poland

⁶  University of Sydney, Faculty of Veterinary Science, Centre for Advanced Technologies in Animal Genetics and Reproduction-ReproGen, Camden, Australia

⁷  Weatherby?s Ireland Blood Typing Laboratory, Johnstown NAAS, Co. Kildare, Ireland

⁸  Institute of Genetics and Animal Breeding, PAS, Jastrzebiec, Wolka Kosowska, Mrokow, Poland

⁹  University of Pretoria, Faculty of Veterinary Science, Onderstepoort, Republic of South Africa

¹⁰  Japan Racing Association, Equine Research Institute, Utsunomiya, Japan

¹¹  Department of Evolutionary Biology and Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden

¹²  Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA

¹³  Department of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, Oslo, Norway

¹⁴  Animal Health Trust, Lanwades Hall, Kentford, Newmarket, Suffolk, United Kingdom

¹⁵  Department of Molecular Genetics, Laboratory of Racing Chemistry, Utsunomiya, Japan

A comprehensive male linkage map was generated by adding 359 new, informative microsatellites to the International Equine Gene Map half-sibling reference families and by combining genotype data from three independent mapping resources: a full sibling family created at the Animal Health Trust in Newmarket, United Kingdom, 8 half-sibling families from Sweden and two half-sibling families from the University of California, Davis. Because the combined data were derived primarily from half-sibling families, only autosomal markers were analyzed. The map was constructed from a total of 766 markers distributed on the 31 equine chromosomes. It has a higher marker density than that of previously reported maps, with 626 markers linearly ordered and 140 other markers assigned to a chromosomal region. Fifty-nine markers (7%) failed to meet the criteria for statistical evidence of linkage and remain unassigned. The map spans 3740 cM with an average distance of 6.3 cM between markers. Fifty-five percent of the intervals are less than 5 cM and only 3% are greater than 20 cM. The current map provides a single resource for genome scan analyses and integration with radiation hybrid map