DDX4 Gene – Function, Expression, Mutations & Clinical Significance

DDX4 (DEAD-box helicase 4) encodes an ATP-dependent RNA helicase belonging to the DEAD-box protein family. It is specifically expressed in germ cells and is essential for gametogenesis, including spermatogenesis and oogenesis. DDX4 is involved in RNA metabolism, including translation initiation, RNA splicing, and ribosome biogenesis. Mutations and altered expression of DDX4 are associated with infertility and certain cancers, particularly germ cell tumors.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• RNA helicase activity in germ cell development

• PIWI-interacting RNA (piRNA) pathway (indirect)

• mRNA surveillance pathway

DDX4 (VASA) is a 724-amino acid DEAD-box RNA helicase predominantly expressed in germ cells. It contains conserved helicase domains (DEADc and HELICc) and an RGG box for RNA binding. The protein localizes to cytoplasmic granules (P-bodies) and the nucleus, where it unwinds RNA secondary structures to facilitate translation and RNA metabolism. DDX4 is essential for germline specification and maintenance; its absence leads to sterility in model organisms. In humans, DDX4 mutations cause non-obstructive azoospermia and premature ovarian failure. Overexpression is observed in germ cell tumors, making it a potential diagnostic marker.