Sequences were determined for codominant RAPD markers closely linked to the Ve locus, a dominant verticillium wilt resistance gene in tomato. Analysis of the sequences linked to Ve and ve revealed a perfectly homologous sequence with a central polymorphic region comprising 79 nucleotide substitutions, insertions, and deletions. Codominant and allele-specific SCARs were developed using conserved and polymorphic sequences linked to the Ve locus. High resolution linkage analysis using F2 progeny segregating for resistance and marker-assisted selection indicated that linkage between the genetic markers and the Ve locus is less than 0.67 +/- 0.49 cM. Sequences were useful in determining the molecular structure of a polymorphic genomic region closely linked to the Ve locus and in developing genetic markers that facilitated marker-assisted selection of the resistant, susceptible, heterozygous, and homozygous genotypes.