Density profiles for genomic elements along the length of Arabidopsis chromosome 1. Local densities were estimated based upon 50 kb (blue lines) and 1 Mb (red lines) enumerative bins and the density profiles were plotted as the number of structures per 50 kb length of chromosome vs. physical distance as measured from the p-terminal of the chromosome. (a) Genes. (b) Indels. (c) SNPs. (d) Retrotransposons. (e) 180 bp repeats. (f) CCSs. The centromeric region was located at about 15 Mb from the p-terminus. The discontinuity indicated along each X-axis is indicative of the gap in the physical map at this region. Although the lines and axes are drawn continuously in these graphs we must remember that there remains large gaps within the centromeric regions of each chromosome which have not been completely defined.