Isolation of cDNAs from maternal mRNAs specifically present during early development.

In many animals the regulation of early embryonic development is under the control of mRNAs of maternal origin. We describe here the construction and characterization of a subtractive cDNA library to isolate genes whose expression is restricted to early development. Such genes might be potentially involved in developmental diseases, if accidentally expressed during adult life. Seven yet unknown genes preferentially expressed in the oocyte and present during early development were isolated from this library by differential screening. Their transcription patterns provide evidence for a selective expression during oogenesis and the existence of a gene family specifically implicated in functions linked to early embryogenesis.