The analysis of linkage disequilibrium (LD) underpins the development of effective genotyping technologies, trait mapping and understanding of biological mechanisms such as those driving recombination and the impact of selection. We apply the Malécot-Morton model of LD to create additive LD maps which describe the high-resolution LD landscape of commercial chickens. We investigated LD in chickens (Gallus gallus) at the highest resolution to date for broiler, white egg and brown egg layer commercial lines. There is minimal concordance between breeds of fine scale LD patterns (correlation coefficient &lt; 0.21), and even between discrete broiler lines. Regions of LD breakdown, which may align with recombination hotspots, are enriched near CpG islands and transcription start sites (p &lt; 2.2x10-16), consistent with recent evidence described in finches, but concordance in hotspot locations between commercial breeds is only marginally greater than random. As in other birds functional elements in the chicken genome are associated with recombination, but, unlike evidence from other bird species, the LD landscape is not stable in the populations studied. The development of optimal genotyping panels for genome-led selection programmes will depend on careful analysis of the LD structure of each line of interest. Further study is required to fully elucidate the mechanisms underlying highly divergent LD patterns found in commercial chickens.,Genotypes from three chicken breedsFiles contain in archive Gallus_genotypes.zip contain genotype data from Pengelly et al, 2016. 'Commercial chicken breeds exhibit highly divergent patterns of linkage disequilibrium'. The three breed types are in separate file: WEL - white egg layers, BEL - brown egg layers, BRO - broilers. Genotypes have been QCed, providing SNPs with an allele frequency &gt; 5%, HWE p &gt; 0.001, and having 95% genotyping rate accross the breed. Genotype data are provided in the PLINK format, see http://pngu.mgh.harvard.edu/~purcell/plink/index.shtml for further details including file format specifications.Gallus_genotypes.zip,</span
