Previously, three proteins have been separately identified as the mouse epidermal growth factor binding protein (EGF-BP). We have identified and sequenced the coding regions of three distinct genes encoding these EGF-BPs from the BALB/c strain. The genes are all members of the glandular kallikrein gene family, which encodes a highly homologous group of serine proteases. Expression of the EGF-BP genes was detected in mouse salivary gland only and was at a relatively similar level for each gene. The isolation of three distinct genes from the one mouse strain indicates that the conflicting data previously reported in the literature are not a result of allelic polymorphisms or strain differences.