Comprehensive linkage map of bovine chromosome 11

International Equine Gene Mapping Workshop Report: a comprehensive linkage map constructed with data from new markers and by merging four mapping resources

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, eight 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 3,740 cM with an average distance of 6.3 cM between markers. Fifty-five percent of the intervals are < or = 5 cM and only 3% > or = 20 cM. The present map demonstrates the cohesiveness of the different data sets and provides a single resource for genome scan analyses and integration with the radiation hybrid map.

Consensus and comprehensive linkage maps of bovine chromosome 24

This study describes development of a consensus genetic linkage map of bovine chromosome 24 (BTA24). Eight participating laboratories contributed data for 58 unique markers including a total of 25 409 meioses. Eighteen markers, which were typed in more than one reference population, were used as potential anchors to generate a consensus framework map. The framework map contained 16 loci ordered with odds greater than 1000:1 and spanned 79.3 cM. Remaining markers were included in a comprehensive map relative to these anchors. The resulting BTA24 comprehensive map was 98.3 cM in length. Average marker intervals were 6.1 and 2.5 cM for framework and comprehensive maps, respectively. Marker order was generally consistent with previously reported BTA24 linkage maps. Only one discrepancy was found when comparing the comprehensive map with the published USDA-MARC linkage map. Integration of genetic information from different maps provides a high-resolution BTA24 linkage map.