SPATA9, spermatogenesis-associated protein 9, or testis development protein NYD-SP16, is a family of eukaryotic proteins associated with sperm production. It is highly expressed in human testis and contains one transmembrane domain. Its localisation indicates it is likely to play an important role in testicular development and spermatogenesis and may be an important factor in male infertility [1].

1: NYD-SP16, a novel gene associated with spermatogenesis of human testis. Cheng LJ, Li JM, Chen J, Ge YH, Yu ZR, Han DS, Zhou ZM, Sha JH; Biol Reprod. 2003;68:190-198. PMID:12493713