SNP distribution on the chromosomes. (A) DNA repeats and SNPs on chromosome I are found mainly on the chromosome arms, whereas similarity with yeast genes is highest on the autosome centers (figure adapted from The C. elegans Sequencing Consortium 1998, p. 2016). The number of SNPs/Mb (B) and the number of sequenced clones/Mb (C) are plotted for the six chromosomes. Autosomes are divided into genetically defined compartments of the left arm (L), the central cluster (C), and the right arm (R) (Barnes et al. 1995; The C. elegans Sequencing Consortium 1998). SNPs occur more frequently on the arms than on the central regions. The X chromosome does not show a higher SNP frequency on the arms.
