Human erythrocyte integral membrane protein band 7 (also termed protein 7.2b or stomatin) is involved in the Na+/K+ permeability of red cells. A cDNA clone coding for this protein was used as a probe to determine the chromosomal localization of the gene (EPB72). Southern blot analysis of somatic cell hybrid DNA panels localized the human EPB72 gene to chromosome band 9q34.1.