RNA-binding protein that plays an essential role in spermatogenesis. May act by binding to the 3'-UTR of mRNAs and regulating their translation. Promotes germ-cell progression to meiosis and formation of haploid germ cells. Defects in DAZ1 may be a cause of spermatogenic failure Y-linked type 2 (SPGFY2). It is a disorder resulting in the absence (azoospermia) or reduction (oligozoospermia) of sperm in the semen, leading to male infertility. AZFc deletions in the Yq11.23 region including the DAZ genes are the most common known genetic cause of human male infertility. Belongs to the RRM DAZ family. Note: This description may include information from UniProtKB.