We have isolated and characterized a cDNA clone containing DNA sequences coding for the noncollagenous carboxy-terminal domain of human pro alpha 2(IV) collagen. Using this cDNA clone in both Southern blot analysis of DNA isolated from human-mouse somatic-cell hybrids and in situ hybridization of normal human metaphase chromosomes, we have demonstrated that the gene coding for human pro alpha 2(IV) collagen is located at 13q33----34, in the same position on chromosome 13 as the pro alpha 1(IV) collagen gene.