Effect of a null mutation of the oviduct-specific glycoprotein gene on mouse fertilization

The mammalian fertilization process takes place in a complex microenvironment within the female genital tract. A member of the chitinase protein family, oviduct-specific glycoprotein (OGP), has been identified in oviductal fluid from various mammalian species, including humans. Although OGP is widely believed to be involved in the process of mammalian fertilization, including spermatozoon function and gamete interactions, based on experimental results obtained in vitro, its physiological significance remains controversial. The present study established OGP gene-null (ogp(-/-)) mice, and primarily characterized their reproductive properties to study the physiological function(s) of OGP. Results obtained from studies using an in vivo or in vitro system showed that the fertility of ogp(-/-) females was within normal limits. These results indicate that OGP is not essential for the process of in vivo fertilization, at least in mice.