We have localized the genes which encode the human type II epidermal keratins K5, K6a, and K6b and the simple epithelial keratin K7 (KRT5, KRT6A, KRT6B, and KRT7, respectively) to chromosome 12 using Southern blot analysis of somatic cell hybrids. In addition, we have sublocalized the genes for K6a and K7 to bands 12q12----q14 on the long arm of this chromosome by in situ hybridization of metaphase chromosomes.