Despite a late start, analysis of the horse genome has progressed rapidly during the past ten years. With synteny, genetic linkage, radiation hybrid, cytogenetic and comparative maps presently generated for all equine chromosomes including the Y chromosome, the map of the equine genome contains approximately 4,000 markers. The average resolution of the mapped markers is approximately 700 kb, which makes the horse gene map the densest among the domestic animal species hitherto not sequenced. This map is currently used by researchers worldwide to discover genes associated with various traits of significance in the horse including overall health, disease resistance, reproduction, fertility, athletic performance, phenotypic characteristics like coat color, etc. Efforts are currently underway to initiate functional studies of the equine genome. Despite in its infancy, the expression based analysis of the equine genome using cDNA or oligoarrays is expected to be an integral part of genome analysis in the horse. More recently, a physical map of approximately 150,000 overlapping bacterial artificial chromosome (BAC) clones is being generated by end-sequencing and subsequent assembly of the BACs. Collectively, the wide range of genomic tools/resources presently available in the horse makes it the next ideal candidate for whole genome sequencing. The motivation and support of the ultimate benefactors - the equine industry - from this huge endeavor will however be pivotal.
